enVision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate

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enVision Math Common Core 6th Grade Answers Key Topic 5 Understand And Use Ratio And

Rate

Topic 5 Essential Question

What are ratios and rates? How can you use ratios and rates to describe quantities and solve problems?

3-ACT MATH

Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 1

Get in Line
It is hard to call it a freeway when you are stuck in the middle of a traffic jam. To keep vehicles moving on the freeway, some on-ramps have traffic signals. Controlling when cars enter the freeway is not only about reducing delays. It can decrease air pollution and collisions.
These ramp meters typically have alternating green and red lights. The time for one cycle depends on the time of day and the amount of traffic on the freeway. Think about this during the 3-Act Mathematical Modeling lesson.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 2

Topic 5 enVision STEM Project

Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 3

Your Task: Get into Gear
Cyclists strive to achieve efficiency during continuous riding. But, which pairing of gears is the best or most efficient? And does the answer change depending on the terrain? You and your classmates will explore gear ratios and how they can affect pedaling and riding speeds.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 4

Topic 5 Get Ready!

Review What You Know!

Vocabulary
Choose the best term from the box to complete each definition.

  • common factor
  • common multiple
  • equivalent fractions
  • fraction

Question 1.
Fractions that name the same amount are called ___________

Answer:
Fractions that name the same amount are called equivalent fractions.

Explanation:
In the above-given question,
given that,
fractions that name the same amount are called equivalent fractions.
for example:
1/2 = 2/4.
2 x 1 = 2.
2 x 2 = 4.

Understand And Use Ratio And Rate 1

Question 2.
The number 3 is a ___________ of 9 and 12.

Answer:
The number 3 is a factor of 9 and 12.

Explanation:
In the above-given question,
given that,
the number 3 is a factor of 9 and 12.
for example:
G.C.F of 9 and 12 = 3.
H.C.F of 9 and 12 = 3.

Question 3.
A number that can be used to describe a part of a set or a part of a whole is a(n) ___________

Answer:
A number that can be used to describe a part of a set or a part of a whole is a(n) common factor.

Explanation:
In the above-given question,
given that,
A number that can be used to describe a part of a set or a part of a whole is a(n) common factor.
for example:
G.C.F of 9 and 12 = 3.
H.C.F of 9 and 12 = 3.

Equivalent Fractions

Write two fractions equivalent to the given fraction.
Question 4.
\(\frac{3}{4}\)

Answer:
The two fractions are equivalent to the 3/4 = 9/12 and 27/36.

Explanation:
In the above-given question,
given that,
the fraction is 3/4.
the two fractions are equivalent to 3/4 is:
27/36 = 3/4.
9/12 = 3/4.

Question 5.
\(\frac{7}{8}\)

Answer:
The two fractions are equivalent to the 7/8 = 14/16 and 21/24.

Explanation:
In the above-given question,
given that,
the fraction is 7/8.
the two fractions are equivalent to 7/8 is:
14/16 = 7/8.
21/24 = 7/8.

Question 6.
\(\frac{12}{5}\)

Answer:
The two fractions are equivalent to the 12/5 = 24/10 and 84/60.

Explanation:
In the above-given question,
given that,
the fraction is 12/5.
the two fractions are equivalent to 12/5 is:
24/10 = 12/5.
84/60 = 12/5.

Understand And Use Ratio And Rate 2

Question 7.
\(\frac{1}{2}\)

Answer:
The two fractions are equivalent to the 1/2 = 2/4 and 3/6.

Explanation:
In the above-given question,
given that,
the fraction is 1/2.
the two fractions are equivalent to 1/2 is:
2/4 = 1/2.
3/6 = 1/2.

Question 8.
\(\frac{8}{9}\)

Answer:
The two fractions are equivalent to the 8/9 = 16/18 and 24/27.

Explanation:
In the above-given question,
given that,
the fraction is 8/9.
the two fractions are equivalent to 8/9 is:
16/18 = 8/9.
24/27 = 8/9.

Question 9.
\(\frac{2}{3}\)

Answer:
The two fractions are equivalent to the 2/3 = 4/6 and 12/9.

Explanation:
In the above-given question,
given that,
the fraction is 2/3.
the two fractions are equivalent to 2/3 is:
4/6 = 2/3.
12/9 = 2/3.

Equation

Write an equation that represents the pattern in each table.
Question 10.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 5

Answer:
The equation is y = 8x.

Explanation:
In the above-given question,
given that,
x contains numbers 2, 3, 4, 5, and 6.
y : 16, 24, 32, 40, and 48.
y = 8x.
16 = 8 x 2.
24 = 8 x 3.
32 = 8 x 4.
40 = 8 x 5.
48 = 8 x 6.

Question 11.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 6

Answer:
The equation is y = 2x + 1.

Explanation:
In the above-given question,
given that,
x : 2, 4, 6, 8, and 10.
y : 5, 7, 9, 11, and 13.
y = 2x + 1.
5 = 2(2) + 1.
7 = 2(4) – 1.
9 = 2(6) – 3.

Understand And Use Ratio And Rate 3

Units of Measure.

Choose the best unit of measure by writing inch, foot, yard, ounce, pound, ton, cup, quart, or gallon.
Question 12.
serving of trail mix

Answer:
The serving of a trail mix can be measured in cups.

Explanation:
In the above-given question,
given that,
Serving of a trail mix.
for example:
nutrition facts are also measured in cups.

Question 13.
height of a person

Answer:
The height of a person can be measured in feet.

Explanation:
In the above-given question,
given that,
the height of a person can be measured in feet.
for example:
the height of the short girl is 5 feet.
the height of the tall girl is 5.6 feet.

Question 14.
weight of a newborn kitten

Answer:
The weight of a newborn kitten can be measured in ounces.

Explanation:
In the above-given question,
given that,
the weight of a newborn kitten can be measured in ounces.
for example:
newborn kittens usually weigh about 3.5 ounces.
a healthy kitten should gain at least 10 grams per day.

Question 15.
gasoline

Answer:
Gasoline can be measured in cubic feet.

Explanation:
In the above-given question,
given that,
Gasoline can be measured in cubic feet.
for example:
gas is sometimes measured in cubic feet at a temperature of 60 degrees Fahrenheit and an atmospheric pressure of 14.7 pounds per square inch.

Measurement Conversions

Question 16.
Michael is 4 feet tall. Explain how Michael could find his height in inches. Then explain how he could find his height in yards.

Answer:
The height in inches = 48.
the height in yards = 12 yards.
Explanation:
In the above-given question,
given that,
Michael is 4 feet tall.
1 feet = 12 inches.
12 x 4 = 48 inches.
1 yard = 3 feets.
3 x 4 = 12 feets.

Language Development

A bag contains the following marbles:
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 7

Complete each math statement.
The following ratio statement reads, for every 1 red marble, there are ___2_____ yellow marbles.
A ratio that compares the yellow marbles to the green marbles is ___6_____ to ____4____.
3 : 4 is the ratio of red marbles to____green____ marbles.
The following ratio statement reads, for every 1 blue marble, there are 2 ___yellow_____ marbles.
\(\frac{3}{2}\) represents the ____ratio____ of red marbles to blue marbles.
4 to 15 is the ratio of green marbles to the ___total_____ number of marbles.
In the ratio of yellow marbles to blue marbles, 6:2, the quantities 6 and 2 are called __ratio______
A __ratio______ compares one ___quantity_____ to another ___quantity_____.

Pick A Project

PROJECT 5A
What animal would you most like to have as a pet?
PROJECT: COMPARE COSTS OF PET FOODS
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 8

Answer:
The animal I would most like to have as a pet is the dog.

Explanation:
In the above-given question,
given that,
the animal I would most like to have as a pet is the dog.
for example:
the cost of the lams is $1.07.
the cost of the Victor is $1.44.

Understand And Use Ratio And Rate 4

PROJECT 5B
How fast do you think you can throw a baseball?
PROJECT: ANALYZE A SPORT STATISTIC
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 9

PROJECT 5C
What color would you want to paint a room?
PROJECT: EXPERIMENT WITH COMBINATIONS OF COLORS
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 10

Answer:
The color I would like to paint a room is cream color.

Explanation:
In the above-given question,
given that,
the color I would like to paint a room is cream color.
for example:
there are many different colors.
they are cream, red, pink, blue, and orange.

PROJECT 5D
If you could visit any U.S. National Park, which would it be?
PROJECT: PLAN A TOUR
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 11

Answer:
I could visit the Yellowstone National Park.

Explanation:
In the above-given question,
given that,
the Yellowstone national park wilderness and recreation area with active geysers like old faithful, plus canyons, rivers, and lakes.
so I could visit the Yellowstone national park.
the area of Yellowstone national park is 8,991 sq km.

Lesson 5.1 Understand Ratios

Explore It!
A band just released an album that contains both pop songs and R&B (rhythm and blues) songs.

I can… use a ratio to describe the relationship between two quantities.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 12

A. How can you describe the relationship between the number of pop songs and the number of R&B songs on the album?

Answer:
The relationship between the number of pop songs and the number of R&B songs is 3: 6.

Explanation:
In the above-given question,
given that,
there are 9 pop songs.
there are 6 R&B songs.
the relationship between the number of pop songs and the number of R&B songs is 9 and 6.
9 : 6 = 3 : 6.
3 x 3 = 9.
3 x 2 = 6.
so the relationship between the number of pop songs and the number of R&B songs is 3: 6.

B. How does the bar diagram represent the relationship between the number of pop songs and the number of R&B songs?
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 13

Answer:
The bar diagram represents the relationship between the number of pop songs and the number of R&B songs is 3: 6.

Explanation:
In the above-given question,
given that,
there are 9 pop songs.
there are 6 R&B songs.
the relationship between the number of pop songs and the number of R&B songs is 9 and 6.
9 : 6 = 3 : 6.
3 x 3 = 9.
3 x 2 = 6.
so the relationship between the number of pop songs and the number of R&B songs is 3: 6.

Focus on math practices
Reasoning Another album has 2 pop songs and 10 R&B songs. Draw a bar diagram that you could use to represent the relationship between the number of pop songs and the number of R&B songs.

Answer:
The relationship between the number of pop songs and the number of R&B songs = 1: 5.

Explanation:
In the above-given question,
given that,
Another album has 2 pop songs and 10 R&B songs.
2 : 10 = 1 : 5.
so the relationship between the number of pop songs and the number of R&B songs = 1: 5.

Understand And Use Ratio And Rate 5

Essential Question
What is a mathematical way to compare quantities?

Try It!

What are three ways to write the ratio of the number of dogs to the total number of pets?

Answer:
The ratio of the number of dogs to the total number of pets = 3: 3.

Explanation:
In the above-given question,
given that,
the ratio of a number of dogs to the total number of pets is same.
for example:
3 : 3.
1: 1.

Convince Me! Is the ratio of dogs to cats the same as the ratio of cats to dogs? Explain.

Try It!

Chen’s friend Alisa can ride her bike 2 miles in 7 minutes. Use a bar diagram or a double number line diagram to find how long it would take Alisa to ride 10 miles if she rides at the same rate.

Answer:
The longer it would take Alisa to ride 10 miles = 70 minutes.

Explanation:
In the above-given question,
given that,
Chen’s friend Alisa can ride her bike for 2 miles in 7 minutes.
2 x 7 = 14 minutes.
10 x 7 = 70 minutes.
so the longer it would take Alisa to ride 10 miles = 70 minutes.

KEY CONCEPT
A ratio compares two quantities. A ratio can be written 3 ways: x to y, x:y, or Ratios can be represented using bar diagrams and double number line diagrams.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 14

Do You Understand?
Question 1.
Essential Question What is a mathematical way to compare quantities?

Answer:
A ratio compares two quantities.
A ratio can be written in 3 ways: x to y, x: y, and x and y.

Explanation:
In the above-given question,
given that,
A ratio compares two quantities.
a ratio can be written in 3 ways are x to y.
x: y, and x/y.
so ratio compares two quantities.

Question 2.
Reasoning What are two different types of comparisons that a ratio can be used to make?

Answer:
The two different types of comparisons that a ratio can be used to make are x:y and x/y.

Explanation:
In the above-given question,
given that,
the ratio is x: y.
x to y.
x/y.
so the two different types of comparisons that a ratio can be used to make are x: y and x / y.

Question 3.
A science classroom has 5 turtles and 7 frogs. What is the ratio of frogs to total animals?
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 15

Answer:
The ratio of frogs to total animals is 7: 12.

Explanation:
In the above-given question,
given that,
A science classroom has 5 turtles and 7 frogs.
there are 7 frogs in the science classroom.
totally there are 12 animals.
frogs: animals.
7: 12.
so the ratio of frogs to total animals is 7: 12.

Understand And Use Ratio And Rate 6

Question 4.
Tye is making trail mix with 3 cups of nuts for every 4 cups of granola. If Tye has 6 cups of nuts, how many cups of granola should he use?

Answer:
The number of cups of granola should use = 2: 3.

Explanation:
In the above-given question,
given that,
Tye is making trail mix with 3 cups of nuts for every 4 cups of granola.
6 : 3 = 2 : 3.
so the number of cups of granola should use = 2: 3.

Do You Know How?
In 5-7, use three different ways to write a ratio for each comparison.

A sixth-grade basketball team has 3 centers, 5 forwards, and 6 guards.
Question 5.
Forwards to guards

Answer:
Forwards to guards = 5: 6.

Explanation:
In the above-given question,
given that,
A sixth-grade basketball team has 3 centers, 5 forwards, and 6 guards.
Forwards to guards:
5: 6.

Question 6.
Centers to total players

Answer:
Centers to total players= 3: 14.

Explanation:
In the above-given question,
given that,
Centers to total players.
the total number of players = 14.
centers to total players = 3: 14.

Question 7.
Guards to centers

Answer:
Guards to centers = 6 : 3.

Explanation:
In the above-given question,
given that,
there are 6 Guards and 3 Guards.
6 : 3 = 2 : 3.
so Guards to centers = 6 : 3.

Question 8.
The ratio of blue cards to green cards is 2 to 5. There are 8 blue cards. Complete the diagram and explain how you can find the number of green cards.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 16

Answer:
The number of blue cards to the number of green cards = 8: 11.

Explanation:
In the above-given question,
given that,
The ratio of blue cards to green cards is 2 to 5.
There are 8 blue cards.
the number of green cards is 11.
so the number of blue cards to the number of green cards = 8: 11.

Practice & Problem Solving

In 9-14, use the data to write a ratio for each comparison in three different ways.

A person’s blood type is denoted with the letters A, B, and O, and the symbols + and -. The blood type A+ is read as A positive. The blood type B- is read as B negative.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 17

Question 9.
O+ donors to A+ donors

Answer:
O+ donors to A+ donors = 2 : 1.

Explanation:
In the above-given question,
given that,
A person’s blood type is denoted with the letters A, B, and O, and the symbols + and -.
O+ donors to A+ donors.
there are 90 O+ donors.
there are 45 A+ donors.
90 : 45 = 2 : 1.

Question 10.
AB-donors to AB+ donors

Answer:
AB- donors to AB+ donors = 2 : 3.

Explanation:
In the above-given question,
given that,
A person’s blood type is denoted with the letters A, B, and O, and the symbols+ and -.
AB- donors to AB+ donors.
there are 4 AB- donors.
there are 6 AB+ donors.
4 : 6 = 2 : 3.
so AB- donors to AB+ donors = 2 : 3.

Question 11.
B+ donors to total donors

Answer:
B+ donors to total donors = 20 : 195.

Explanation:
In the above-given question,
given that,
totally there are 195 donors.
B+ donors to total donors.
20: 195.

Question 12.
O- donors to A-donors

Answer:
O- donors to A- donors = 9 : 21.

Explanation:
In the above-given question,
given that,
O- donors to A- donors.
there are 9 O- donors.
there are 21 A- donors.
O- donors to A- donors = 9 : 21.

Question 13.
A+ and B+ donors to AB+ donors

Answer:
A+ and B+ donors to AB+ donors = 6 : 65.

Explanation:
In the above-given question,
given that,
A+ and B+ donors to AB+ donors.
there are A+ and B+ donors who are 65.
there are  6 AB+ donors.
A+ and B+ donors to AB+ donors = 6 : 65.

Question 14.
A- and B-donors to AB- donors

Answer:
A- and B- donors to AB- donors = 21: 4.

Explanation:
In the above-given question,
given that,
there are 21 A- donors.
there are 0 B- donors.
there are 4 AB- donors.
so A- and B- donors to AB- donors = 21: 4.

Question 15.
Which comparison does the ratio \(\frac{90}{9}\) represent?

Answer:
The ratio 90/9 represent = 10 : 1.

Explanation:
In the above-given question,
given that,
the ratio 90/9 represents.
90 : 9 = 10: 1.
so the ratio represent = 10 : 1.

Question 16.
Which comparison does the ratio 20:21 represent?

Answer:
The comparison does the ratio 20:21 represent = B+ and A-.

Explanation:
In the above-given question,
given that,
there are 20 B+ donors.
there are 21 A- donors.
so the ratio 20:21 represent = B+ and A+.

Question 17.
Sam is packing gift boxes with fruit. For each apple, he packs 3 plums and 5 oranges. If he puts 3 apples in a box, how many plums and oranges will Sam put in the box? Draw a diagram to solve the problem.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 18

Answer:
The number of plums and oranges will Sam put in the box is 9:15.

Explanation:
In the above-given question,
given that,
Sam is packing gift boxes with fruit.
For each apple, he packs 3 plums and 5 oranges.
1:3, 2:6, and 3:9.
1:5, 2:10, and 3:15.
so the number of plums and oranges will Sam put in the box is 9:15.

Question 18.
Write a ratio that compares the number of teal squares to the total number of squares in the quilt.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 19

Answer:
The ratio that compares the number of teal squares to the total number of squares in the quilt = 1:3.

Explanation:
In the above-given question,
given that,
there are 18 teal squares and 6 squares.
6 : 18 = 1:3.
so the ratio that compares the number of teal squares to the total number of squares in the quilt = 1:3.

Question 19.
Reasoning Rita’s class has 14 girls and 16 boys. How does the ratio 14:30 describe Rita’s class?

Answer:
The ratio 14:30 describes there are 7 girls and 15 boys.

Explanation:
In the above-given question,
given that,
Rita’s class has 14 girls and 16 boys.
there are 14 girls and 16 boys.
there are 14 girls and 30 boys.
14: 30 = 7:15.
so there are 7 girls and 15 boys.

Question 20.
A math class surveyed students about their musical preferences and recorded the results in the table. Use the data to write a ratio for each comparison in three different ways.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 20
a. Students who prefer classical to students who prefer techno

Answer:
The students who prefer classical to students who prefer techno is 1:3.

Explanation:
In the above-given question,
given that,
there are 4 classical students.
there are 12 techno students.
4 : 12 = 1:3.
so the students who prefer classical to students who prefer techno is 1:3.

b. Students who prefer hip-hop to total number of students surveyed

Answer:
Students who prefer hip-hop to the total number of students surveyed = 15:53.

Explanation:
In the above-given question,
given that,
there are 15 hip-hop students.
the total number of students is 53.
so the ratio is 15:53.

Question 21.
Construct Arguments Justin used blocks to model the following situation: A car dealership sells 7 cars for every 4 minivans it sells. How can Justin use his model to find the number of minivans the dealership sells if it sells 35 cars?
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 21

Answer:
The number of minivans the dealership sells if it sells 35 cars = 20 minivans.

Explanation:
In the above-given question,
given that,
A car dealership sells 7 cars for every 4 minivans it sells.
35/7 = 5.
4 x 5 = 20.
so the number of minivans the sealership sells if it sells 35 cars = 20 minivans.

Question 22.
Make Sense and Persevere The ratio of adult dogs to puppies at a dog beach in Florida on Monday was 3:2. There were 12 puppies there that day. On Tuesday, 15 adult dogs were at the dog beach. What is the difference between the number of adult dogs at the dog beach on Monday and Tuesday?

Answer:
The difference between the number of adult dogs at the dog beach on Monday and Tuesday = 1:3.

Explanation:
In the above-given question,
given that,
The ratio of adult dogs to puppies at a dog beach in Florida on Monday was 3:2.
There were 12 puppies there that day.
On Tuesday, 15 adult dogs were at the dog beach.
12:15 = 4:5.
4:5 – 3:2 = 1:3.
so the difference between the number of adult dogs at the dog beach on Monday and Tuesday = 1:3.

Question 23.
Higher Order Thinking At 9:30 A.M., Sean started filling a swimming pool. At 11:30 A.M., he had filled 1,800 gallons. At what time will the pool be full?
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 22

Answer:
At 2:30 P.M the pool will fill completely.

Explanation:
In the above-given question,
given that,
At 9:30 A.M., Sean started filling a swimming pool.
At 11:30 A.M., he had filled 1,800 gallons.
for 2 hours it will fill 1800 gallons.
1800 + 1800 = 3600.
3600 + 900 = 4500.
so at 2:30 P.M the pool will fill completely.

Assessment Practice

Question 24.
The diagram below represents the relationship between the number of students taking Spanish and the number of students taking French in a foreign language class.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 23
What is the ratio of the number of students taking Spanish to the number of students taking French?
A. 8 : 3
B. 8 : 5
C. 8 : 8
D. 8 : 13

Answer:
The ratio of the number of students taking Spinach to the number of students taking French = 8: 5.

Explanation:
In the above-given question,
given that,
the number of Spanish students is 8.
the number of French students is 5.
the ratio is 8:5.
so the ratio of a number of students taking spinach to the number of students taking french = 8:5.

Lesson 5.2 Generate Equivalent Ratios

Solve & Discuss It!
Sally used all of the paint shown below to make a certain tint of orange paint. How many pints of red paint should be mixed with 24 pints of yellow paint to make the same tint of orange?
I can… use multiplication and division to find equivalent ratios.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 24

Look for Relationships
How can you use the relationship between the number of pints of yellow paint and the number of pints of red paint to answer the question?

Answer:
The ratio of yellow paint to the red paint is 4:3.

Explanation:
In the above-given question,
given that,
the number of yellow paint is 4.
the number of red paint is 3.
the relationship between the number of pints of yellow paint and the number of pints of red paint is 4:3.

Focus on math practices
Reasoning If Sally uses the same ratio of yellow paint to red paint, how many pints of yellow paint should she mix with 16 pints of red paint?

Essential Question
How can you find equivalent ratios?

Try It!

If you extend the table above, how would you find the next ratio of basketball players to soccer players?
Answer:

Convince Me! What is the relationship between the number of basketball players and the number of soccer players in each column in the table?

Try It!

Rashida uses 8 cups of tomatoes and 3 cups of onions to make salsa. How many cups of onions should Rashida use if she uses only 4 cups of tomatoes?

Answer:
Rashida use 1.5 cups of onions when she use 4 cups of tomatoes.

Explanation:
In the above-given question,
given that,
Rashida uses 8 cups of tomatoes and 3 cups of onions to make salsa.
for 1.5 cups of onions is used for 4 cups of tomatoes.
4 : 1.5.
so the ratio is 4:1.5.

Try It!

Which of the following ratios are equivalent to 16:20?
2:3, 4:5, 18:22, 20:25

Answer:
The ratio 4:5 equal to 16:20.

Explanation:
In the above-given question,
given that,
the ratios are 2:3, 4:5, 18:22, and 20:25.
16: 20 = 4:5.
so the ratio 4:5 equal to 16:20.

KEY CONCEPT
You can multiply or divide both terms of a ratio by the same nonzero number to find equivalent ratios.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 25

Do You Understand?
Question 1.
Essential Question How can you find equivalent ratios?

Answer:
We can multiply or divide both terms of a ratio by the same nonzero number to find equivalent ratios.

Explanation:
In the above-given question,
given that,
multiply both terms by same non-zero number.
divide both terms by same non-zero number.
for example:
30 x 2 = 60.
40 x 2 = 80.

Question 2.
Critique Reasoning Deshawn says that the ratios 3:5 and 5:7 are equivalent ratios because by adding 2 to both terms of 3:5 you get 5:7. Is Deshawn correct? Explain.

Answer:
No, he was not correct.

Explanation:
In the above-given question,
given that,
Deshawn says that the ratios 3:5 and 5:7 are equivalent ratios because by adding 2 to both terms of 3:5 you get 5:7.
3:5 and 9:15.
so he was not correct.

Question 3.
What are two ways you can find an equivalent ratio for \(\frac{12}{16}\)?

Answer:
The equivalent ratio for 12/16 is 3:4.

Explanation:
In the above-given question,
given that,
the ratio is 12/16.
12: 16 = 3:4.
so the ratio is 3:4.

Question 4.
How can you show that the ratios 10:4 and 15:6 are equivalent?

Answer:
The ratios are not equal.

Explanation:
In the above-given question,
given that,
the ratios are 10:4 and 15:6.
10 : 4 = 15:6.
so the ratios are not equal.

Do You Know How?
Question 5.
Complete the table using multiplication to find ratios that are equivalent to 4:5.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 26

Answer:
The ratios are 8:10, 12:15, and 16:20.

Explanation:
In the above-given question,
given that,
the ratio is 4:5.
8 : 10 = 4:5.
12:15 = 4:5.
16:20 = 4:5.

Question 6.
Complete the table using division to find ratios that are equivalent to 40:28.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 27

Answer:
The ratios that are equivalent to 40:28 = 20:14 and 10:7.

Explanation:
In the above-given question,
given that,
the numbers are 40/28.
40/28 = 20/14.
40/28 = 10/7.
so the ratios that are equivalent to 40:28 = 20:14 and 10:7.

In 7-10, write an equivalent ratio for each given ratio.
Question 7.
\(\frac{12}{21}\)

Answer:
The equivalent ratio is

Explanation:
In the above-given question,
given that,
the ratio is 12/21.

Question 8.
1:3

Answer:
The equivalent ratio is 3:9.

Explanation:
In the above-given question,
given that,
the ratio is 1:3.
3:9 = 1:3.
3 x 1 = 3.
3 x 3 = 9.
so the equialent ratio is 3:9.

Question 9.
6 to 8

Answer:
The equivalent ratio is 3:4.

Explanation:
In the above-given question,
given that,
the ratio is 6 to 8.
6/8 = 3/4.
so the ratio is 3/4.
2 x 3 = 6.
2 x 4 = 8.

Question 10.
Pi (st) can be approximated using decimals as the ratio 3.14:1. Find 3 ratios equivalent to the ratio 3.14:1.

Answer:
The equivalent ratio is 22/7:1.

Explanation:
In the above-given question,
given that,
the ratio is 3.14:1.
22/7 = 3.14.
22/7:1 = 3.14:1.

Practice & Problem Solving

Question 11.
Eva is making French toast. How many ounces of milk should Eva use with 10 eggs?
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 28

Answer:
The recipe uses 10, 15, 20, 25, and 30.

Explanation:
In the above-given question,
given that,
for 2 eggs the recipe uses 5 ounces of milk.
for 4 eggs the recipe uses 10 ounces of milk.
for 6 eggs the recipe uses 15 ounces of milk.
for 8 eggs the recipe uses 20 ounces of milk.
for 10 eggs the recipe uses 25 ounces of milk.

In 12-15, write three ratios that are equivalent to the given ratio.
Question 12.
\(\frac{6}{7}\)

Answer:
The three ratios are 3/14 and 18/21.

Explanation:
In the above-given question,
given that,
the ratio is 6/7.
3/14 = 6/7.
18/21 = 6/7.
so the three ratios are 3/14 and 18/21.

Question 13.
\(\frac{9}{5}\)

Answer:
The three ratios are 27/15 and 18/10.

Explanation:
In the above-given question,
given that,
the ratio is 9/5.
18/10 = 9/5.
27/15 = 9/5.

Question 14.
8:14

Answer:
The three ratios are 16/28 and 24/42.

Explanation:
In the above-given question,
given that,
the ratio is 8/14.
16/28 = 8/14.
24/42 = 8/14.
so the three ratios are 16/28 and 24/42.

Question 15.
7:9

Answer:
The three ratios are 6/28 and 21/27.

Explanation:
In the above-given question,
given that,
the ratio is 7/9.
6/28 = 7/9.
21/27 = 7/9.

Question 16.
A teacher kept track of what students consumed at a school picnic. For three grades, the ratios of the amount of water consumed to the amount of fruit juice consumed were equivalent. Complete the table.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 29

Answer:
The juice contains 21 and 28 gallons.

Explanation:
In the above-given question,
given that,
A teacher kept track of what students consumed at a school picnic.
For three grades, the ratios of the amount of water consumed to the amount of fruit juice consumed were equivalent.
for 6th grade 24 gallons of water contains the juice 28 gallons.
for 7th grade 18 gallons of water contains the juice 21 gallons.
so the juice contains 21 and 28 gallons.

Question 17.
The attendant at a parking lot compared the number of hybrid vehicles to the total number of vehicles in the lot during a weekend. The ratios for the three days were equivalent. Complete the table.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 30

Answer:
The ratios for the three days were equivalent is 28 and 72.

Explanation:
In the above-given question,
given that,
The attendant at a parking lot compared the number of hybrid vehicles to the total number of vehicles in the lot during a weekend.
the ratios for the three days were equivalent.
28 and 72 are the equivalent ratio.

Question 18.
Shiloh is sharing jellybeans. The jar of jellybeans has the ratio shown. If Shiloh keeps the ratio the same and gives his friend 7 pink jellybeans, how many green jellybeans should he also share?
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 31

Answer:
The number of green jellybeans should he also share =

Explanation:
In the above-given question,
given that,
Shiloh is sharing jellybeans.
The jar of jellybeans has the ratio shown.
If Shiloh keeps the ratio the same and gives his friend 7 pink jellybeans.

Question 19.
Use Appropriate Tools Equivalent ratios can be found by extending pairs of rows or columns in a multiplication table. Write three ratios equivalent to \(\frac{2}{5}\) using the multiplication table.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 32

Answer:
The three ratios equivalent to 2/5 are 4/10 and 6/15.

Explanation:
In the above-given question,
given that,
the ratio is 2/5.
4/10 = 2/5.
6/15 = 2/5.
so the three ratios equivalent to 4/10 and 6/15.

Question 20.
If 5 mi ≈ 8 km, about how many miles would be equal to 50 km? Explain.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 33

Answer:
The number of miles is equal to 31.069 miles.

Explanation:
In the above-given question,
given that,
5 miles ≈ 8 km.
50 km is equal to 31.069 miles.
so 31.069 miles is equal to 50 km.

Question 21.
Vocabulary How is the word term defined when used to describe a ratio relationship? How is the word term defined in the context of an expression?

Answer:
The term is one of the two numbers in the ratio a to b.
where a is the first term and b is the second term.

Explanation:
In the above-given question,
given that,
The term is one of the two numbers in the ratio a to b.
where a is the first term and b is the second term.
it is also used to indicate each one of the 4 numbers in a proportion.
if a = c.
then a,b,c, and d are the terms of the proportion.

Question 22.
Higher Order Thinking Three sisters are saving for a special vacation in Orlando, Florida. The ratio of Ada’s savings to Ellie’s savings is 7:3, and the ratio of Ellie’s savings to Jasmine’s savings is 3:4. Together all three girls have saved $56. How much has each girl saved? Complete the table. Explain how the table can be used to solve the problem.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 34

Answer:
The Ada’s savings are $14 and $28.
Ellie’s savings are $3, $9, and $12.
Jasmine’s savings are $8 and $12.

Explanation:
In the above-given question,
given that,
Three sisters are saving for a special vacation in Orlando, Florida.
The ratio of Ada’s savings to Ellie’s savings is 7:3, and the ratio of Ellie’s savings to Jasmine’s savings is 3:4.
Together all three girls have saved $56.
7 x 2 = 14, 7 x 4 = 28.
3 x 1 = 3, 3 x 3 = 9, and 3 x 4 = 12.
4 x 2 = 8, 4 x 3 = 12, and 4 x 4 = 16.

Assessment Practice

Question 23.
Corey is making key lime pies for the school fair. For every 3 egg yolks, he uses 2 tablespoons of key lime zest.
PART A
Complete the table to find equivalent ratios.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 35

Answer:
The egg yolks are 6, 9, and 12.

Explanation:
In the above-given question,
given that,
Corey is making key lime pies for the school fair.
For every 3 egg yolks, he uses 2 tablespoons of key lime zest.
the equivalent ratios are 6, 9, and 12.
so the egg yolks are 6, 9, and 12.

PART B
How can you use the table to find how many egg yolks are needed for 8 tablespoons of lime zest?

Answer:
The number of egg yolks are 12 needed for 8 tablespoons of lime zest.

Explanation:
In the above-given question,
given that,
Corey is making key lime pies for the school fair.
For every 3 egg yolks, he uses 2 tablespoons of key lime zest.
3 x 1 = 3, 3 x 2 = 6, 3 x 3 = 9, and 3 x 4 =12.
so the number of egg yolks are 12 needed for 8 tablespoons of lime zest.

Question 24.
Which ratios can be represented by Pi (t)? Select all that apply.
☐ Diameter : Circumference
☐ Circumference : Diameter
☐ Circumference : Radius
☐ Radius : Circumference
☐ Circumference : Twice the radius

Answer:
Options A and B are correct.

Explanation:
In the above-given question,
given that,
diameter and circumference are represented.
so options A and B are correct.

Lesson 5.3 Compare Ratios

Solve & Discuss It!
Scott is making a snack mix using almonds and raisins. For every 2 cups of almonds in the snack mix, there are 3 cups of raisins. Ariel is making a snack mix that has 3 cups of almonds for every 5 cups of sunflower seeds. If Scott and Ariel each use 6 cups of almonds to make a batch of snack mix, who will make a larger batch?

I can… compare ratios to solve problems.
Envision Math Common Core 6th Grade Answer Key Topic 5 Understand And Use Ratio And Rate 36

Model with Math
How can you use ratio tables to represent Scott’s and Ariel’s snack mixes?

Focus on math practices
Look for Relationships Scott and Ariel want to make as much snack mix as possible, but no more than 25 cups of mix. If they can use only full cups of ingredients, who can make more mix without going over?

Essential Question
How can you compare ratios to solve a problem?

Try It!

Marlon had 6 hits in 15 at bats. How does Marlon’s hits to at bats ratio compare to Adrian’s?

Answer:
The ratio is 2:5.

Explanation:
In the above-given question,
given that,
Marlon had 6 hits in 15 at bats.
6 : 15 = 2:5.
so the ratio is 2:5.

Convince Me! Based on their hits to at bats ratios, who would you expect to have more hits in a game, Marlon or Dustin? Explain.

Try It!

Tank 3 has a ratio of 3 guppies for every 4 angelfish. Complete the ratio table to find the number of angelfish in Tank 3 with 12 guppies.
Using the information in Example 2 and the table at the right, which tank with guppies has more fish?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 37

Answer:
The number of Guppies is 6, 9, and 12.
the number of Angelfish is 8, 12, and 16.

Explanation:
In the above-given question,
given that,
Tank 3 has a ratio of 3 guppies for every 4 angelfish.
3 x 1 = 3.
3 x 2 = 6.
3 x 3 = 9.
3 x 4 = 12.
4 x 1 = 4.
4 x 2 = 8.
4 x 3 = 12.
4 x 4 = 16.

KEY CONCEPT
You can use ratio tables to compare ratios when one of the corresponding terms is the same.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 38

Do You Understand?
Question 1.
Essential Question How can you compare ratios to solve a problem?

Answer:
We can use ratio tables to compare ratios when one of the corresponding terms is the same.

Explanation:
In the above-given question,
given that,
we can use ratio tables to compare ratios when one of the corresponding terms is the same.
for example:
5 x 2 = 10.
5 x 3 = 15.
5 x 4 = 20.

Question 2.
In Example 1, how many hits would Adrian have in 50 at bats? Explain.

Answer:

Question 3.
Reasoning During the first week of a summer camp, 2 out of 3 campers were boys. During the second week, 3 out of 5 campers were boys. There were 15 total campers each week. During which week were there more boy campers? Explain.

Answer:
In the second week, there are more boy campers.

Explanation:
In the above-given question,
given that,
During the first week of a summer camp, 2 out of 3 campers were boys.
During the second week, 3 out of 5 campers were boys.
There were 15 total campers each week.
so in the second week, there are more boy campers.

Do You Know How?
Question 4.
To make plaster, Kevin mixes 3 cups of water with 4 pounds of plaster powder. Complete the ratio table. How much water will Kevin mix with 20 pounds of powder?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 39

Answer:
The amount of Kevin mix with 20 pounds of powder = 15 cups of water.

Explanation:
In the above-given question,
given that,
To make plaster, Kevin mixes 3 cups of water with 4 pounds of plaster powder.
3 x 2 = 6.
3 x 3 = 9.
3 x 4 = 12.
3 x 5 = 15.
so the amount of Kevin mix with 20 pounds of powder = 15 cups of water.

Question 5.
Jenny makes plaster using a ratio of 4 cups of water to 5 pounds of plaster powder. Whose plaster recipe uses more water? Use the ratio table here and in Exercise 4 to compare.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 40

Answer:
16 cups of water to 20 pounds of powder.

Explanation:
In the above-given question,
given that,
Jenny makes plaster using a ratio of 4 cups of water to 5 pounds of plaster powder.
8 cups of water to 10 pounds of powder.
12 cups of water to 15 pounds of powder.
16 cups of water to 20 pounds of powder.

Question 6.
Kevin and Jenny each use 12 cups of water to make plaster. Who will make more plaster? Explain.

Answer:
Kevin makes more plaster than Jenny.

Explanation:
In the above-given question,
given that,
Kevin and Jenny each use 12 cups of water to make plaster.
Kevin uses 12 cups of water to make 20 pounds of plaster.
Jenny uses 12 cups of water to make 15 pounds of plaster.

Practice & Problem Solving

In 7-10, use the ratio table at the right.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 41
Question 7.
Local radio station WMTH schedules 2 minutes of news for every 20 minutes of music. Complete the ratios shown in the table at the right.

Answer:
The ratios are 30/3, 40/4, 50/5, and 60/6.

Explanation:
In the above-given question,
given that,
20 minutes of music is equal to 2 minutes of news.
20/2 = 10.
30/3 = 10.
40/4 = 10.
50/5 = 10.
60/6 = 10.
so the ratios are 30/3, 40/4, 50/5, and 60/6.

Question 8.
What is the ratio of minutes of music to minutes of news?

Answer:
The ratio of minutes of music to minutes of news = 10:1.

Explanation:
In the above-given question,
given that,
20 minutes of music is equal to 2 minutes of news.
20/2 = 10.
30/3 = 10.
40/4 = 10.
50/5 = 10.
60/6 = 10.
so the ratios are 30/3, 40/4, 50/5, and 60/6.

Question 9.
Radio station WILM broadcasts 4 minutes of news for every 25 minutes of music. Which radio station broadcasts more news each hour?

Answer:
The radio station broadcasts more news each hour =

Explanation:
In the above-given question,
given that,
Radio station WILM broadcasts 4 minutes of news for every 25 minutes of music.

Question 10.
Which station will have to be on the air longer to broadcast 4 minutes of news? Explain.

Answer:
The station will have to be on the air longer to broadcast 4 minutes of news = 40 minutes of music.

Explanation:
In the above-given question,
given that,
20 minutes of music is equal to 2 minutes of news.
20/2 = 10.
30/3 = 10.
40/4 = 10.
50/5 = 10.
60/6 = 10.
so the station will have to be on the air longer to broadcast 4 minutes of news = 40 minutes of music.

Question 11.
Reasoning The ratio tables at the right show the comparison of books to games for sale at Bert’s Store and at Gloria’s Store. Complete the ratio tables. Which store has the greater ratio of books to games? Explain.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 42

Answer:
The ratio of Bert’s store is 5/7, 6/8, 7/9, and 8/10.
The ratio of Gloria’s store is 5/8, 6/9, 7/12, 8/15, and 9/18.

Explanation:
In the above-given question,
given that,
The ratio tables at the right show the comparison of books to games for sale at Bert’s Store and at Gloria’s Store.
the ratios of Bert’s store are 5/7, 6/8, 7/9, and 8/10.
the ratio of Gloria’s store is 5/8, 6/9, 7/12, 8/15, and 9/18.

Question 12.
The ratio of soy sauce to lime juice in a homemade salad dressing is 7:6. The ratio of soy sauce to lime juice in a store-bought dressing is 11:9. Which dressing has the greater ratio of soy sauce to lime juice?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 43

Answer:
The ratio of Soy sauce to Lime juice is 7:6, 8:7, 9:8, 10:9, and 11:10.
the ratio of Soy sauce to lime juice is 11:9, 12:10, 13:11, 14:12, and 15:13.

Explanation:
In the above-given question,
given that,
The ratio of soy sauce to lime juice in a homemade salad dressing is 7:6.
The ratio of soy sauce to lime juice in a store-bought dressing is 11:9.
the ratio of soy sauce to the Lime juice is 7:6, 8:7, 9:8, 10:9, and 11:10.
the ratio of soy sauce to lime juice is 11:9, 12:10, 13:11, 14:12, and 15:13.

Question 13.
One bouquet of flowers has 3 milkweeds for every 5 tickseeds. Another bouquet has 4 tickseeds for every 5 canna lilies. If both bouquets have 20 tickseeds, which bouquet has more flowers?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 44

Answer:
Bouquet 4 has more flowers.

Explanation:
In the above-given question,
given that,
One bouquet of flowers has 3 milkweeds for every 5 tickseeds.
Another bouquet has 4 tickseeds for every 5 canna lilies.
3 x 5 =15.
4 x 6 = 24.
5 x 7 = 35.
6 x 8 = 48.
7 x 9 = 63.
4 x 5 = 20.
5 x 6 = 30.
6 x 7 = 42.
7 x 8 = 56.
8 x 9 = 72.

Question 14.
Higher Order Thinking Lauren can drive her car 320 miles on 10 gallons of gasoline. Melissa can drive her car 280 miles on 8 gallons of gasoline. Who can drive farther on 40 gallons of gasoline? Complete the ratio tables to justify your solution.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 45

Answer:

Explanation:
In the above-given question,
given that,
Lauren can drive her car 320 miles on 10 gallons of gasoline.
Melissa can drive her car 280 miles on 8 gallons of gasoline.
320/10 and 280/8.

Assessment Practice

Question 15.
Fran buys Florida cone seashells in packages that contain 9 purple-dyed Florida cone seashells for every 3 pink-dyed Florida cone seashells. Mia buys Florida cone seashells in packages with a ratio of 2 pink-dyed Florida cone seashells to 4 purple-dyed Florida cone seashells.
PART A
Complete the tables using the ratios given.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 46

 

Answer:
The missing ratios of Fran’s shell packages are 18/6, 27/9, and 36/12.
the missing ratios of Mia’s shell packages are 8/4, 12/6, and 16/8.

Explanation:
In the above-given question,
given that,
Fran buys Florida cone seashells in packages that contain 9 purple-dyed Florida cone seashells for every 3 pink-dyed Florida cone seashells.
6 x 3 = 18, 3 x 3 = 9, 9 x 3 = 27, and 12 x 3 = 36.
2 x 2 = 4, 4 x 2 = 8, 6 x 2 = 12, and 8 x 2 = 16.

PART B
If the girls each buy packages that contain 6 pinkdyed Florida cone seashells, how many purple-dyed Florida cone seashells would each have? Explain.

Answer:
The number of purple-dyed Florida cone seashells would each have = 18.

Explanation:
In the above-given question,
given that,
If the girls each buy packages that contain 6 pink dyed Florida cone seashells.
6 x 3 = 18.
so the number of purple-dyed Florida cona seashells would each have = 18.

Lesson 5.4 Represent and Graph Ratios

Solve & Discuss It!
For every 4 adults at the beach one afternoon, there were 3 children. How many children were at the beach if there were 8, 12, 16, or 20 adults at the beach?

I can… solve ratio problems by using tables and graphs to show equivalent ratios.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 47

Model with Math
How does the graph show the ratio?

Answer:
The graph shows the ratio y = x-1, y = x-2, y = x-4.

Explanation:
In the above-given question,
given that,
For every 4 adults at the beach one afternoon, there were 3 children.
if there were 8 adults there were 6 children.
if there were 12 adults there were 9 children.
4 x 1 = 4, 4 x 2 = 8, 4 x 3 = 12, and 4 x 4 = 16.
3 x 1 = 3, 3 x 2 = 6, 3 x 3 = 9, and 3 x 4 = 12.

Focus on math practices
Critique Reasoning There were 25 children and 15 adults at the beach. Emery said that there were 5 children for every 3 adults. Is he correct? Explain.

Answer:
Yes, Emery was correct.

Explanation:
In the above-given question,
given that,
There were 25 children and 15 adults at the beach.
Emery said that there were 5 children for every 3 adults.
3 x 5 = 15.
for 15 adults there were 25 children.
so Emery was correct.

Essential Question
How can you use tables and graphs to show equivalent ratios?

Try It!

What are the coordinates of the point that represents the number of balloons you can buy for $6?

Answer:
The coordinates of the point that represents the number of balloons we can but for $6 is (6,0) and (0,6).

Explanation:
In the above-given question,
given that,
for example:
for example:
the points are (6, 0) and (0,6).

Convince Me! How can you use the graph to find the cost of 15 balloons?

Try It!

Can you draw an object with a diameter of 10 inches and a circumference of 50 inches? Explain.

Answer:
Yes, we can draw a diameter of 10 inches and a circumference of 50 inches.

Explanation:
In the above-given question,
given that,
we can draw a diameter of 10 inches and a circumference of 50 inches.
the circumference is the center of the circle.
radius is half of the diameter.
diameter is 50/2 = 25.
so we can draw a diameter.

KEY CONCEPT
You can use ratio tables and graphs to show equivalent ratios. When ordered pairs representing equivalent ratios are graphed as points in the coordinate plane, they form a line.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 48

Do You Understand?
Question 1.
Essential Question How can you use tables and graphs to show equivalent ratios?

Answer:
When ordered pairs representing equivalent ratios are graphed as points in the coordinate plane, they form a line.

Explanation:
In the above-given question,
given that,
for example:
for every 3 tennis rackets sold, 4 tennis balls are sold.
for every 12 tennis rockets sold, 16 tennis balls are sold.
so when ordered pairs representing equivalent ratios are graphed as points in the coordinate plane, they form a line.

Question 2.
Look for Relationships In Example 2, how could you use the graph to find the number of apples needed for 30 celery sticks?

Answer:
The number of apples needed for 30 celery sticks = 40 apples.

Explanation:
In the above-given question,
given that,
if there are 30 celery sticks, there would be 40 apples.
3 x 10 = 30.
4 x 10 = 40.
so the number of apples needed for 30 celery sticks = 40 apples.

Question 3.
How could you use repeated addition to show ratios equivalent to 1:3 on a graph?

Answer:
The ratios forms a straight line.

Explanation:
In the above-given question,
given that,
for example:
for every 3 tennis rackets sold, 4 tennis balls are sold.
for every 12 tennis rockets sold, 16 tennis balls are sold.
so when ordered pairs representing equivalent ratios are graphed as points in the coordinate plane, they form a line.

Do You Know How?
Question 4.
Complete the table to show equivalent ratios representing a cost of $8 for every 3 boxes. Then write the pairs of values as points to be plotted on a coordinate plane.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 49

Answer:
The points are (12, 32) and (15, 40).

Explanation:
In the above-given question,
given that,
3 x 2 = 6, 3 x 3 = 9, 3 x 4 = 12, and 3 x 5 = 15.
8 x 2 = 16, 8 x 3 = 24, 8 x 4 = 32, and 8 x 5 = 40.
so the coordinate points are (12, 32) and (15, 40).

Question 5.
Model with Math Plot the equivalent ratios (3, 4), (6, 8), and (9, 12) on the graph. Use the graph to find the number of nonfiction books purchased if 10 fiction books are purchased.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 50

Answer:
The number of nonfiction books purchased if 10 fiction books are purchased = 14.

Explanation:
In the above-given question,
given that,
the equivalent ratios are (3, 4), (6, 8), (9, 12), and (10, 14).
the points form a straight line.
so the number of nonfiction books purchased if 10 fiction books are purchased = 14.

Practice & Problem Solving

Leveled Practice in 6 and 7, complete the table and graph the pairs of values.
Question 6.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 51

Answer:
The points are (6, 9).

Explanation:
In the above-given question,
given that,
The points are (2,3) and (4,6).
2 x 2 = 4, 2 x 3 = 6.
3 x 2 = 6, 3 x 3 = 9.
so the points are (6, 9).

Question 7.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 52

Answer:
The points are (50, 20).

Explanation:
In the above-given question,
given that,
the points are (5, 2) and (25, 10).
5 x 5 = 25, 5 x 10 = 50.
2 x 5 = 10, 2 x 10 = 20.
so the points are (50, 20).

Question 8.
A student runs 2 minutes for every 10 minutes she walks.
a. Complete the table. Graph the pairs of values.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 53

Answer:
The points are (6, 30).

Explanation:
In the above-given question,
given that,
the running minutes are 2, 4.
the walking minutes are 10, 20.
2 x 2 = 4.
2 x 3 = 6.
10 x 2 = 20.
10 x 3 = 30.
so the points are (6, 30).

b. For how long would the student walk if she runs for 7 minutes?

Answer:
The student walks if she runs for 7 minutes = 35.

Explanation:
In the above-given question,
given that,
the running minutes are 2, 4.
the walking minutes are 10, 20.
2 x 2 = 4.
2 x 3 = 6.
10 x 2 = 20.
10 x 3 = 30.
so the student walks if she runs for 7 minutes = 35.

Question 9.
A car magazine reports the number of miles driven for different amounts of gas for three cars. Which car travels the farthest on 1 gallon of gas? Explain.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 54

Answer:
Car A can travels the farthest on 1 gallon of gas.

Explanation:
In the above-given question,
given that,
Car A can travels for 1 gallon of gas the number of miles driven is 50.
Car B can travels for 1 gallon of gas the number of miles driven is 30.
Car C can travels for 1 gallon of gas the number of miles driven is 25.
So car A can travels the farthest on 1 gallon of gas.

Question 10.
Model with Math A bread recipe calls for 4 cups of white flour for every 5 cups of whole-wheat flour. Complete the table to show how many cups of whole-wheat flour are needed to mix with 16 cups of white flour. Then graph the pairs of values.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 55

Answer:
The points of whole-wheat flour are 4, 8, 12, and 16.

Explanation:
In the above-given question,
given that,
A bread recipe calls for 4 cups of white flour for every 5 cups of whole-wheat flour.
4 x 1 = 4, 4 x 2 = 8, 4 x 3 = 12, and 4 x 4 = 16.
so the points of whole-wheat flour is 4, 8, 12, and 16.

Question 11.
The graph shows the relationship between the number of cups of sugar and the number of cups of flour in a key-lime bread recipe. What point on the graph represents the number of cups of sugar that would be used with 8 cups of flour?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 56

Answer:
The number of cups of sugar that would be used with 8 cups of flour is 2.

Explanation:
In the above-given question,
given that,
the flour(c) is on the x-axis.
the sugar (c) is on the y-axis.
the points are (2, 0.5), (4, 1), (6, 1.5), (8, 2), (10, 2.5),  (12, 3), and (14, 3.5).
so the number of cups of sugar that would be used with 8 cups of flour is 2.

Question 12.
Higher Order Thinking Ishwar can read 5 pages in 15 minutes. Anne can read 15 pages in 1 hour. Explain how you could use a table or graph to find how much longer it would take Anne to read a 300-page book than Ishwar.

Answer:
The much longer it would take Anne to read a 300-page book than Ishwar = 20 hours.

Explanation:
In the above-given question,
given that,
Ishwar can read 5 pages in 15 minutes.
Anne can read 15 pages in 1 hour.
30 pages in 2 hours.
60 in 4 hours.
90 in 6 hours.
90 + 90 = 180 pages in 12 hours.
8 hours is 120 pages.
12 + 8 = 20 hours.

Assessment Practice

Question 13.
The measurements of a circular object are given in the ratio table.
PART A
Find the missing dimensions of other circular objects by completing the ratio table.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 57

Answer:
The missing dimensions are 42 and 301.

Explanation:
In the above-given question,
given that,
The measurements of a circular object are given in the ratio table.
the missing dimensions are 42 and 301.

PART B
Graph the pairs of values.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 58

Answer:
The points are (200, 200), (400, 400), (600, 600), and (800, 800).

Explanation:
In the above-given question,
given that,
the diameter is shown on the x-axis.
the circumference is shown on y-axis.
so the points are (200, 200), (400, 400), (600, 600), and (800, 800).

Topic 5 Mid-Topic Checkpoint

Question 1.
Vocabulary How can a ratio be used to compare quantities? Lesson 5-1
Answer:

Question 2.
The circumference of the outside of a ring is 66 mm, and it has an outer diameter of 21 mm. If the circumference of the inside of the ring is 50 mm, what is the inner diameter of the ring? Lesson 5-4

Answer:
The inner diameter of the ring = 50 mm.

Explanation:
In the above-given question,
given that,
The circumference of the outside of a ring is 66 mm, and it has an outer diameter of 21 mm.
If the circumference of the inside of the ring is 50 mm.
the inner diameter of the ring = 50 mm.

Question 3.
During the breakfast service, the D-Town Diner sells 12 cups of coffee for every 10 glasses of orange juice. How many cups of coffee would the diner have sold if 40 glasses of orange juice had been sold? Complete the table with equivalent ratios. Lesson 5-2
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 59

Answer:
The ratios are (24, 20), (36, 30), and (48,40).

Explanation:
In the above-given question,
given that,
During the breakfast service, the D-Town Diner sells 12 cups of coffee for every 10 glasses of orange juice.
2 x 5 = 10, and 2 x 6 = 12.
3 x 10 = 30, and 3 x 12 = 36.
4 x 10 = 40, and 4 x 12 = 48.
so the ratios are (24, 20), (36, 30), and (48, 40).

Question 4.
The ratio of cows to chickens at Old McDonald’s Farm is 2:7. Select all the farms that have a greater ratio of cows to chickens than Old McDonald’s Farm. Lessons 5-3
☐ Red’s Farm: 3 cows for every 5 chickens
☐ Pasture Farm: 2 cows for every 9 chickens
☐ Cluck & Moo Farm: 1 cow for every 5 chickens
☐ C & C Farm: 3 cows for every 8 chickens
☐ T Family Farm: 1 cow for every 3 chickens

Answer:

Question 5.
A package of 3 notebooks costs $5. Complete the ratio table and graph the pairs of values. How much will 18 notebooks cost? Lesson 5-4
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 60

Answer:
The cost of 18 notebooks is $30.

Explanation:
In the above-given question,
given that,
A package of 3 notebooks costs $5.
3 x 2 = 6, 3 x 3 = 9, 3 x 4 = 12, 3 x 5 =15, 3 x 6 = 18.
5 x 2 = 10, 5 x 3 = 15, 5 x 4 = 20, 5 x 5 = 25, 5 x 6 = 30.
so the cost of 18 notebook is $30.

Topic 5 Mid-Topic Performance Task

Hillsdale Orchard grows Fuji apples and Gala apples. There are 160 Fuji apple trees and 120 Gala apple trees in the orchard.

PART A
Hillsdale Orchard’s owners decide to plant 30 new Gala apple trees. Complete the ratio table to find the number of new Fuji apple trees the owners should plant if they want to maintain the same ratio of Fuji apple trees to Gala apple trees.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 61

Answer:
The number of Fuji Apple trees to the Gala Apple trees is (40,30), (80, 60), and (160,120).

Explanation:
In the above-given question,
given that,
Hillsdale Orchard’s owners decide to plant 30 new Gala apple trees.
30 x 2 = 60.
60 x 2 = 120.
40 x 2 = 80.
80 x 2 = 160.
so the number of Fuji Apple trees to the Gala Apple trees is (40,30), (80, 60), and (160, 120).

PART B
Use the ratio table to complete a graph that shows the relationship between the number of Fuji apple trees and Gala apple trees at Hillsdale Orchard.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 62

Answer:
Fuji Apple trees on the x-axis.
Gala Apple trees on the y-axis.

Explanation:
In the above-given question,
given that,
Fuji Apple trees on the x-axis.
Gala Apple trees on the y-axis.
the points are (80, 60), (160, 120), and (240, 180).

PART C
By the end of the next season, the owners of Hillsdale Orchard plan to have 240 Fuji apple trees. Explain how you could use the graph to find the total number of Fuji and Gala apple trees that Hillsdale Orchard will have if the owners achieve their goal.

Answer:
The total number of Fuji and Gala apple trees that Hillsdale Orchard is (240, 180).

Explanation:
In the above-given question,
given that,
the owners of Hillsdale Orchard plan to have 240 Fuji apple trees.
the points are (80, 60), (160, 120), and (240, 180).
so the total number of Fuji and Gala apple trees that Hillsdale Orchard is (240, 180).

Lesson 5.5 Understand Rates and Unit Rates

Solve & Discuss It!
What is the cost of 10 bottles of fruit juice?

I can… solve problems involving rates.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 63

Make Sense and Persevere
How can you use tables or diagrams to make sense of the quantities in the problem?

Focus on math practices
Critique Reasoning Monica says, “If 4 bottles cost $10, then 2 bottles cost $5, and 8 bottles cost $20. So 10 bottles cost $5 + $20.” Is Monica correct? Explain.

Answer:
No Monica was not correct.

Explanation:
In the above-given question,
given that,
If 4 bottles cost $10, then 2 bottles cost $5, and 8 bottles cost $20.
4 bottles cost $10.
8 bottles cost $20.
10 bottles cost $30.
so Monica was not correct.

Essential Question
What are rates and unit rates?

Try It!

At the same rate, how long would it take the car to travel 60 kilometers?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 64
It will take the car _______ minutes to travel ________ kilometers.

Answer:
It will take the car 6 minutes to travel 60 kilometers.

Explanation:
In the above-given question,
given that,
10 x 6 = 60.
3 x 6 = 18.
it will take the car 6 minutes to travel 60 kilometers.

Convince Me! Sal draws the double number line diagram at the right. He says it shows that at this rate the race car will travel 35 kilometers in 10.5 minutes. Critique Sal’s reasoning. Is he correct? Explain.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 65

Answer:
Yes, he was correct.

Explanation:
In the above-given question,
given that,
Sal draws the double number line diagram at the right.
He says it shows that at this rate the race car will travel 35 kilometers in 10.5 minutes.
the points are (3, 10), (6, 20), (9, 30), (10.5, 35), and (12, 40).
so he was correct.

Try It!

A recipe for scrambled eggs uses 2 tablespoons of milk for every 3 eggs. What are two unit rates that could represent the recipe?

Answer:
The two-unit rates that could represent the recipe = 2/3, 4/6, and 6/9.

Explanation:
In the above-given question,
given that,
A recipe for scrambled eggs uses 2 tablespoons of milk for every 3 eggs.
2 x 2 = 4, 2 x 3 = 6, 2 x 4 = 8.
3 x 2 = 6, 3 x 3 = 9, 3 x 4 = 12.
so the two-unit rates that could represent the recipe = 2/3, 4/6, and 6/9.

Try It!

A canoeing club travels 78 miles in 3 days. How far could they travel in 5 days if they maintain the same speed?

Answer:
They can travel 130 miles in 5 days.

Explanation:
In the above-given question,
given that,
A canoeing club travels 78 miles in 3 days.
78 miles in 3 days.
78/3 = 26.
26 + 26 = 52.
78 + 52 = 130.
so they can travel 130 miles in 5 days.

KEY CONCEPT
A rate compares quantities with unlike units of measure.
\(\frac{\$ 3.50}{7 \text { oranges }}\)
A unit rate compares a quantity to 1 unit of another quantity.
\(\frac{\$ 3.50}{7 \text { oranges }}=\frac{\$ 0.50}{1 \text { orange }}\)

Do You Understand?
Question 1.
Essential Question What are rates and unit rates?

Answer:
A rate compares quantities with unlike units of measure.
A unit rate compares a quantity to 1 unit of another quantity.

Explanation:
In the above-given question,
given that,
A rate compares quantities with unlike units of measure.
A unit rate compares a quantity to 1 unit of another quantity.
for example:
3.50/7 = 0.5.

Question 2.
Be Precise Use what you know about ratios to describe a rate.

Answer:
A rate compares quantities with unlike units of measure.
A unit rate compares a quantity to 1 unit of another quantity.

Explanation:
In the above-given question,
given that,
A rate compares quantities with unlike units of measure.
A unit rate compares a quantity to 1 unit of another quantity.
for example:
3.50/7 = 0.5.

Question 3.
Reasoning A bathroom shower streams 5 gallons of water in 2 minutes.
a. Find the unit rate for gallons per minute and describe it in words.

Answer:
The unit rate for gallons per minute is 2.5.

Explanation:
In the above-given question,
given that,
A bathroom shower streams 5 gallons of water in 2 minutes.
5/2 = 2.5.
so the unit rate for gallons per minute.

b. Find the unit rate for minutes per gallon and describe it in words.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 66

Answer:
The unit rate for minutes per gallon = 2.5.

Explanation:
In the above-given question,
given that,
A bathroom shower streams 5 gallons of water in 2 minutes.
5/2 = 2.5.
so the unit rate for gallons per minute.

Do You Know How?
In 4 and 5, find the value of n.
Question 4.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 67

Answer:
The number of hours for n = 12.

Explanation:
In the above-given question,
given that,
the number of hours is 4 for the number of miles = 45.
45 + 45 + 45 = 135.
4 + 4 + 4 = 12.
so for the n hours the number of miles = 12.

Question 5.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 68

Answer:
The value of n is 4.

Explanation:
In the above-given question,
given that,
the cost in dollars are shown in the figure.
the pounds are also shown.
for 2 dollars the pounds count is 1.
for 3 dollars the pounds count is 2.
for 4 dollars the pounds count is 3.
for 5 dollars the pounds count is 4.
so the value of n is 4.

Question 6.
Jenny packaged 108 eggs in 9 cartons. Write this statement as a rate.

Answer:
Jenny packaged 108 eggs in 2 cartons.

Explanation:
In the above-given question,
given that,
Jenny packaged 18 eggs in 9 cartons.
18/9 = 2.
so the Jenny packaged 108 eggs in 9 cartons is 2.

Question 7.
Anna Maria read 40 pages in 60 minutes. What is her unit rate in pages per minute?

Answer:
The unit rate in pages per minute = 0.6.

Explanation:
In the above-given question,
given that,
Anna Maria read 40 pages in 60 minutes.
40/60 = 4/6.
2/3 = 0.6.
so the unit rate in pages per minute = 0.6.

In 8 and 9, use the unit rates that you found in Exercise 3.
Question 8.
How many gallons of water does the shower stream in 6 minutes?

Answer:
The number of gallons of water does the shower stream in 6 minutes = 6.6.

Explanation:
In the above-given question,
given that,
40/6 = 20/3.
20/3 = 6.6.
so the number of gallons of water does the shower stream in 6 minutes = 6.6.

Question 9.
How long can someone shower to use only 10 gallons of water?

Answer:
The shower to use only 10 gallons of water = 0.5.

Explanation:
In the above-given question,
given that,
the long can someone shower to use only 10 gallons of water.
10/20 = 1/2 = 0.5.
so the length can someone shower to use only 10 gallons of water = 0.5.

Practice & Problem Solving

In 10 and 11, write each statement as a rate.
Question 10.
Jan saw 9 full moons in 252 days.

Answer:
The rate is 0.03.

Explanation:
In the above-given question,
given that,
Jaw saw 9 full moons in 252 days.
9/252 = 0.03.
so the rate is 0.03.

Question 11.
It took Hannah 38 minutes to run 8 laps.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 69

Answer:
The rate is 4.75.

Explanation:
In the above-given question,
given that,
It took Hannah 38 minutes to run 8 laps.
38/8 = 4.75.
so the rate is 4.75.

In 12 and 13, find the value of x.
Question 12.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 70

Answer:
The value of x is 8.

Explanation:
In the above-given question,
given that,
the number of bowls is 2.
the number of fish in 2 bowls is 16.
the number of bowls is 6.
the number of fish in 6 bowls is 48.
48/6 = 8.
so the value of x is 8.

Question 13.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 71

Answer:
The value of x is 46.

Explanation:
In the above-given question,
given that,
the number of miles and the number of hours are given.
the number of miles for 4 is 46.
the number of miles for 8 is 92.
the number of miles for 12 is 138.
the number of miles for 16 is 184.

In 14 and 15, find the unit rate.
Question 14.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 72

Answer:
The number of miles is 20.

Explanation:
In the above-given question,
given that,
320 mi/16 gal.
320/16 / 16/16.
20/1 = 20.
so the number of miles is 20.

Question 15.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 73

Answer:
The value of cm = 15.

Explanation:
In the above-given question,
given that,
75 cm to 5 h.
75/5 / 5/5.
15 / 1 = 15.
so the value of the cm = 15.

In 16-19, complete each table.
Question 16.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 74

Answer:
The missing values are 2, 5, 5.

Explanation:
In the above-given question,
given that,
the minutes on the number of pages are given.
9 x 2 = 18.
1 x 2 = 2.
5 x 2 =10.
5 x 3 = 15.

Question 17.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 75

Answer:
The missing values are 62, 434, and 682.

Explanation:
In the above-given question,
given that,
186/3 = 62.
62/1 = 62.
434/7 = 62.
682/11 = 62.
so the missing values are 62, 434, and 682.

Question 18.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 76

Answer:
The missing values are 12.3, 61.5, and 10.

Explanation:
In the above-given question,
given that,
12.3/1 = 12.3.
24.6/2 = 12.3.
61.5/5 =12.3.
123/10 = 12.3.
so the missing values are 12.3, 61.5, and 10.

Question 19.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 77

Answer:
The missing values are 1, 75, 300.

Explanation:
In the above-given question,
given that,
the number of gallons and miles are given.
125/5 = 25.
25/1 = 25.
75/3 = 25.
300/12 = 25.
so the missing values are 1, 75, and 300.

Question 20.
Which runner set the fastest pace? Explain.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 78

Answer:
Allison runs at the fastest pace.

Explanation:
In the above-given question,
given that,
the runner Martha did 20 laps in 32 min.
the runner Allison did 16 laps in 25 min.
the runner Rachel did 17 laps in 27.2 min.
speed = distance/time.
Martha = 20/32.
Martha = 0.625.
Allison = 16/25.
Allison = 0.64.
Rachel = 17/27.2.
Rachel = 0.625.
Allison runs at the fastest pace.

Question 21.
Model with Math Over the summer, Alexis read 15 books in 12 weeks. The diagram below can be used to track her progress. If Alexis read at the same rate each week, how many books had she read in 4 weeks? In 8 weeks? Complete the diagram.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 79

Answer:
The missing books are 5 and 10.

Explanation:
In the above-given question,
given that,
Over the summer, Alexis read 15 books in 12 weeks.
Alexis read the 5 books in 4 weeks.
the number of books Alexis read in 8 weeks = 10.
5 x 1 = 5.
5 x 2 = 10.
5 x 3 = 15.
so the missing books are 5 and 10.

Question 22.
An elephant charges an object that is 0.35 kilometer away. How long will it take the elephant to reach the object?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 80

Answer:
The distance will it take the elephant to reach the object = 0.5 km.

Explanation:
In the above-given question,
given that,
An elephant charges an object that is 0.35 kilometers away.
Elephants can charge at speeds of 0.7 km per minute.
0.35/0.7 = 0.5.
7 x 5 = 35.
so the distance will it take the elephant to reach the object = 0.5 km.

Question 23.
A machine takes 1 minute to fill 6 cartons of eggs. At this rate, how many minutes will it take to fill 420 cartons?

Answer:
The number of minutes will it take to fill 420 cartons = 70 min.

Explanation:
In the above-given question,
given that,
A machine takes 1 minute to fill 6 cartons of eggs.
70 x 6 = 420.
420/6 = 70.
so the number of minutes will it take to fill 420 cartons = 70 min.

Question 24.
Higher Order Thinking How are the ratios \(\frac{24 \text { laps }}{1 \text { hour }}\) and \(\frac{192 \text { laps }}{8 \text { hours }}\) alike? How are they different?

Answer:
They are same.

Explanation:
In the above-given question,
given that,
the ratios 24, 192, and 8 are alike.
8 x 1 = 8.
8 x 3 = 24.
24 x 8 = 192.
so they are same.

Assessment Practice

Question 25.
A bakery sells 12 gourmet orange-zest cupcakes for $36.00. Select all the statements that are true.
☐ \(\frac{\$ 3.00}{1 \text { cupcake }}\) is a unit rate for the cost per 1 cupcake cupcake.
☐ \(\frac{36}{12}\) represents the ratio of $36.00 for 12 cupcakes.
☐ Using the same rate, the bakery can sell 6 cupcakes for $20.00.
☐ Using the same rate, the bakery can sell 2 dozen cupcakes for $72.00.
☐ Using the same rate, it would cost $24.50 for 8 cupcakes.

Answer:
Option A is correct.

Explanation:
In the above-given question,
given that,
A bakery sells 12 gourmet orange-zest cupcakes for $36.00.
36/12 = 3.
12 x 3 = 36.
so option A is correct.

Lesson 5.6 Compare Unit Rates

Solve & Discuss It!
Rick and Nikki own remote-control cars. They use a stopwatch to record the speed of each car. Whose car is faster?

I can… compare unit rates to solve problems.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 81

Be Precise
Use precise numbers and units to describe and compare rates.

Focus on math practices
Make Sense and Persevere If each car maintains its rate of speed, how long will it take Rick’s car to travel 300 feet? How long will it take Nikki’s car to travel the same distance? Explain.

Answer:
The long will it take Nikki’s car to travel the same distance = 60 sec.

Explanation:
In the above-given question,
given that,
Rick and Nikki own remote-control cars.
the distance in 30 sec is 150 feet.
the distance will it take 300 feet in 60 sec.
300/150 = 2.
30 x 2 = 60.
so the long will it take Nikki’s car to travel the same distance = 60 sec.

Essential Question
How can you use unit rates to make comparisons?

Try It!

Ashley is Austin’s older sister. She trains in the same pool and can swim 9 laps in 6 minutes. Is Ashley a faster swimmer than Austin?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 82
Ashley swims 1.5 laps per minute. Because ________ 1.4, Ashley is a _______ swimmer than Austin.

Answer:
Ashley swims faster than Austin.

Explanation:
In the above-given question,
given that,
Ashley is Austin’s older sister.
She trains in the same pool and can swim 9 laps in 6 minutes.
Ashley swims 1.5 laps per minute.
9/1.5 = 6.
6/1.4 = 4.2.
so Ashley swims faster than Austin.

Convince Me! How can you use the unit rate in minutes per lap to compare Ashley’s speed to Austin’s speed?

Try It!

Explain how to decide which is the better value, 4 greeting cards for $10 or 6 greeting cards for $14.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 83

Answer:
The better value is 4 greeting cards for $10.

Explanation:
In the above-given question,
given that,
4 greeting cards for $10.
6 greeting cards for $14.
10/4 = 2.5.
14/6 = 2.3.
so the better value is 4 greeting cards for $10.

KEY CONCEPT
You can use unit rates to make comparisons.
$8.50 per hour > $8.00 per hour
\(\frac{32 \mathrm{~cm}}{1 \mathrm{sec}}\) < \(\frac{45 \mathrm{~cm}}{1 \mathrm{sec}}\)

\(\frac{7 \text { laps }}{1 \mathrm{~min}}\) < \(\frac{9 \text { laps }}{1 \mathrm{~min}}\) 175 words per minute > 95 words per minute

Do You Understand?
Question 1.
Essential Question How can you use unit rates to make comparisons?

Answer:
We can use unit rates to make comparisons.

Explanation:
In the above-given question,
given that,
You can use unit rates to make comparisons.
$8.50 per hour > $8.00 per hour.
175 words per minute > 95 words per minute.

Question 2.
Critique Reasoning Paul says that a lower unit rate is a better value only if you can use all the items purchased to get the lower unit rate. Do you agree? Explain.

Answer:
Yes, i will agree.

Explanation:
In the above-given question,
given that,
Paul says that a lower unit rate is a better value only if you can use all the items purchased to get the lower unit rate.
so I will agree.

Question 3.
Reasoning Car A travels 115 miles on 5 gallons of gas. Car B travels 126 miles on 6 gallons of gas. How can you find which car gets better gas mileage?

Answer:
The Car A gets better gas mileage.

Explanation:
In the above-given question,
given that,
Car A travels 115 miles on 5 gallons of gas.
Car B travels 126 miles on 6 gallons of gas.
115/5 = 23.
126/6 = 21.
so car A gets better gas mileage.

Do You Know How?
Question 4.
Hakim’s car travels 600 feet in 20 seconds. Andre’s motorcycle travels 300 feet in 12 seconds. Which is faster, the car or the motorcycle? Explain.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 84
a. Find the unit rates.

Answer:
The car is faster.

Explanation:
In the above-given question,
given that,
Hakim’s car travels 600 feet in 20 seconds.
Andre’s motorcycle travels 300 feet in 12 seconds.
300/12 = 25.
600/20 = 30.
so the car is faster.

b. Compare the unit rates.
Answer:

In 5 and 6, find each unit price.
Question 5.
7 movie tickets for $56

Answer:
Each ticket cost $8.

Explanation:
In the above-given question,
given that,
7 movie tickets for $56.
$56/7 = 8.
so each ticket cost $8.

Question 6.
12 fluid ounces of shampoo for $2.76

Answer:
12 fluid ounces of shampoo for $2.76.

Explanation:
In the above-given question,
given that,
12 fluid ounces of shampoo for $2.76.
12/2.76 = 4.34.
so 12 fluid ounces of shampoo for $2.76.

Question 7.
Which is the better value, 2 books for $15 or 6 books for $45? Explain.

Answer:
Both of them have better value.

Explanation:
In the above-given question,
given that,
2 books for $15.
6 books for $45.
15 + 15 + 15 = 45.
so both of them have the better value.

Practice & Problem Solving

Leveled Practice In 8 and 9, find each unit price.
Question 8.
9 pens for $3.60
\(\frac{\$ 3.60 \div 9}{9 \div 9}=\frac{ }{1}\)

Answer:
9 pens for $3.60 = $2.5.

Explanation:
In the above-given question,
given that,
9 pens for $3.60.
9/3.60 = 2.5.
so 9 pens for $3.60 = $2.5.

Question 9.
15 ounces of canned beans for $2.25
\(\frac{\$ 2.25 \div}{15 \div}=\frac{}{}\)

Answer:
15 ounces of canned beans for $2.25 = 6.6.

Explanation:
In the above-given question,
given that,
15 ounces of canned beans for $2.25.
15/2.25 = 6.6.
so 15 ounces of canned beans for $2.25 = 6.6.

In 10 and 11, determine which is the better value.
Question 10.
3 kilograms of charcoal for $7.95 or 5 kilograms of charcoal for $12.50

Answer:
7.95/3 = 2.65 and 12.50/5 = 2.5.

Explanation:
In the above-given question,
given that,
3 kilograms of charcoal for $7.95.
5 kilograms of charcoal for $12.50.
7.95/3 = 2.65.
12.50/5 = 2.5.

Question 11.
50 envelopes for $2.49 or 90 envelopes for $5.50

Answer:
50 envelopes for $2.49 or 90 envelopes for $5.50 is 16.36.

Explanation:
In the above-given question,
given that,
50 envelopes for $2.49 or 90 envelopes for $5.50.
50/2.49 = 20.08.
90/5.50 = 16.36.

In 12-15, compare the rates to find which is greater.
Question 12.
35 points in 20 minutes or 49 points in 35 minutes

Answer:
35 points in 20 minutes or 49 points in 35 minutes are 1.75 and 1.4.

Explanation:
In the above-given question,
given that,
35 points in 20 minutes or 49 points in 35 minutes.
35/20 = 1.75.
49/35 = 1.4.

Question 13.
12 laps in 8 minutes or 16 laps in 10 minutes

Answer:
16 laps in 10 minutes.

Explanation:
In the above-given question,
given that,
12 laps in 8 minutes or 16 laps in 10 minutes.
12/8 = 1.5.
16/10 = 1.6.
so 16 laps in 10 minutes.

Question 14.
45 strikeouts in 36 innings or 96 strikeouts in 80 innings

Answer:
45 strikeouts in 36 innings or 96 strikeouts in 80 innings = 1.2.

Explanation:
In the above-given question,
given that,
45 strikeouts in 36 innings or 96 strikeouts in 80 innings.
45/36 = 1.25.
96/80 = 1.2.

Question 15.
480 stickers on 6 sheets or 120 stickers on 2 sheets

Answer:
120 stickers on 2 sheets is 60.

Explanation:
In the above-given question,
given that,
480 stickers on 6 sheets or 120 stickers on 2 sheets.
480/6 = 80.
120/2 = 60.
so 120 stickers on 2 sheets is 60.

In 16-18, compare the rates to find which is the better value.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 85
Question 16.
$27 for 4 large pizzas or $32 for 5 large pizzas

Answer:
The both values are same.

Explanation:
In the above-given question,
given that,
$27 for 4 large pizzas or $32 for 5 large pizzas.
$27/4 = $6.75.
$32/5 = $6.4.
so both values are same.

Question 17.
$30 for 100 flyers or $65 for 250 flyers

Answer:
$30 for 100 flyers = 3.3.

Explanation:
In the above-given question,
given that,
$30 for 100 flyers.
$65 for 250 flyers.
100/30 = 3.3.
250/100 = 2.5.

Question 18.
36 pictures for $8 or 24 pictures for $5

Answer:
24 pictures for $5 = 4.8.

Explanation:
In the above-given question,
given that,
36 pictures for $8 or 24 pictures for $5.
36/8 = 4.5.
24/5 = 4.8.
so 24 pictures for $5 = 4.8.

Question 19.
Model with Math Katrina and Becca exchanged 270 text messages in 45 minutes. An equal number of texts was sent each minute. The girls can send 90 more text messages before they are charged additional fees. Complete the double number line diagram. At this rate, for how many more minutes can the girls exchange texts before they are charged extra?
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 86

Answer:
The missing values are 90/6, 180/6, and 360/6.

Explanation:
In the above-given question,
given that,
Katrina and Becca exchanged 270 text messages in 45 minutes.
An equal number of texts was sent each minute.
The girls can send 90 more text messages before they are charged additional fees.
90/6 = 15.
180/6 = 30.
360/6 = 60.
so the missing values are 90/6, 180/6, and 360/6.

Question 20.
Reasoning Which container of milk would you buy? Explain.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 87

Answer:
I will buy 1/2 gallon of milk for $2.29.

Explanation:
In the above-given question,
given that,
1/2 gallon of milk for $2.29.
1 gallon of milk for $3.99.
$2.29/0.5 = 4.58.
$3.99/1 = 3.99.
I will buy 1/2 gallon of milk for $2.29.

Question 21.
Higher Order Thinking Amil and Abe rode in a bike-a-thon. Abe rode for 77 minutes at a faster rate per mile than Amil. Find Amil’s unit rate. Then explain how you could use it to find a possible unit rate for Abe.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 88

Answer:
Abe’s rate is 4.5.

Explanation:
In the above-given question,
given that,
Amil and Abe rode in a bike-a-thon.
Abe rode for 77 minutes at a faster rate per mile than Amil.
77/17 = 4.5.
so Abe’s rate was 4.5.

Assessment Practice

Question 22.
A food warehouse sells cans of soup in boxes. Bargain shoppers have four options.
PART A
Complete the table to find the unit price for each option.
Envision Math Common Core 6th Grade Answers Topic 5 Understand And Use Ratio And Rate 89

Answer:
The unit price is 1.13, 1.17, 1.16, and 1.12.

Explanation:
In the above-given question,
given that,
A food warehouse sells cans of soup inboxes.
12 cans for $10.56 = 1.13.
16 cans for $13.60 = 1.17.
20 cans for $17.20 = 1.16.
24 cans for $21.36 = 1.12.

PART B
Compare the unit rates found in Part A and identify the best value.

Answer:
The best value is 1.17.

Explanation:
In the above-given question,
given that,
A food warehouse sells cans of soup inboxes.
12 cans for $10.56 = 1.13.
16 cans for $13.60 = 1.17.
20 cans for $17.20 = 1.16.
24 cans for $21.36 = 1.12.

Lesson 5.7 Solve Unit Rate Problems

Solve & Discuss It!
Suppose you are traveling by train to visit a friend who lives 275 miles away. How long will the trip take? Moving at a constant speed, how long would it take the train to travel 385 miles?

I can… use unit rates to solve problems.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 90

Model with Math
How can you use what you know about unit rates to model and solve this problem?

Focus on math practices
Reasoning Suppose the train was traveling at a constant speed that is twice as fast as 55 miles per hour. How long would it take the train to go 275 miles? Explain.

Answer:
The long would it take the train to go 275 miles = 5.

Explanation:
In the above-given question,
given that,
Suppose you are traveling by train to visit a friend who lives 275 miles away.
the train travels at a constant speed of 55 miles per hour.
275/55 = 5.
so the long would it take the train to go 275 miles = 5.

Essential Question
How can you use unit rates to solve problems?

Try It!

At the same rate, how far would the jet fly in 75 minutes?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 91
The jet would fly ________ miles.

Answer:
The jet would fly 1 mile.

Explanation:
In the above-given question,
given that,
15 x 5 = 75.
1 minute x 75 = 75.
75 miles/75 minutes = 1.

Convince Me! How could you use the table from Example 1 to find how far the jet would fly in 75 minutes? Explain.

Try It!

Jarod paid $13.80 for 5 tickets to the game. At the same rate, how much would 3 tickets cost?

Answer:
The 3 tickets cost is $8.28.

Explanation:
In the above-given question,
given that,
Jarod paid $13.80 for 5 tickets to the game.
$13.80/5 = $2.76.
$2.76 + $2.76 + $2.76 = $8.28.
so the 3 tickets cost is $8.28.

Try It!

A submarine travels 19 miles in \(\frac{1}{2}\) hour. Write an equation to find out how long it would take the submarine to travel 57 miles at the same rate. Then find the time.

Answer:
The submarine to travel 57 miles at the same rate = 3.

Explanation:
In the above-given question,
given that,
A submarine travels 19 miles in \(\frac{1}{2}\) hour.
19 miles in 0.5 hours.
19 x 3 = 57.
57/19 = 3.
so the submarine to travel 57 miles at the same rate = 3.

KEY CONCEPT
You can use ratio tables or unit rates to solve rate problems, including constant speed problems.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 92

Do You Understand?
Question 1.
Essential Question How can you use unit rates to solve problems?

Answer:
We can use ratio tables to solve rate problems including constant speed problems.

Explanation:
In the above-given question,
given that,
we can use ratio tables to solve rate problems including constant speed problems.
Ant traveled 6 cm in 1.5 sec.
ant traveled 3 cm in 12 sec.
ant traveled 4.5 cm in 18 sec.

Question 2.
Construct Arguments An ostrich runs 6 miles in 12 minutes at a constant speed. Explain how you can use a unit rate to find how far the ostrich could run in 40 minutes.

Answer:
The far ostrich could run in 40 minutes = 8 miles.

Explanation:
In the above-given question,
given that,
An ostrich runs 6 miles in 12 minutes at a constant speed.
40/6 = 8.
so the far ostrich could run in 40 minutes = 8 miles.

Question 3.
Bananas sell for $0.58 per pound. How could you write an equation to show the relationship between the total cost, c, and the number of pounds of bananas, p?

Answer:
C = $0.58p.

Explanation:
In the above-given question,
given that,
Bananas sell for $0.58 per pound.
the total cost is written as c.
the number of pounds is written as p.
c = $0.58p.

Do You Know How?
In 4 and 5, use unit rates to solve.
Question 4.
A football player runs 80 yards in 25 seconds. If he maintains the same rate of speed, how far could he run in 60 seconds?

Answer:
The far could he run in 60 seconds = 1.3.

Explanation:
In the above-given question,
given that,
A football player runs 80 yards in 25 seconds.
80/25 = 3.2.
80/60 = 1.3.
so the far could he run in 60 seconds = 1.3.

Question 5.
On a family vacation, Amy’s dad drove the car at a constant speed and traveled 585 miles in 13 hours. At this rate, how long would it have taken the family to travel 810 miles? What was the car’s rate of speed?

Answer:
The rate of the car’s speed = 45 hours.

Explanation:
In the above-given question,
given that,
Amy’s dad drove the car at a constant speed and traveled 585 miles in 13 hours.
585/13 = 45.
45 x 13 = 585.
so the rate of the car’s speed = 45 hours.

Question 6.
Look at Exercise 5. Write an equation to find the total distance, d, that Amy’s family traveled after t hours.
Answer:

Practice & Problem Solving

Leveled Practice In 7-9, solve the rate problems.
Question 7.
A horse named Northern Dancer won the Kentucky Derby with a time of exactly 2 minutes. At this constant rate, how long would it take Northern Dancer to run the Belmont Stakes?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 93
It would take Northern Dancer ______ minutes to run the Belmont Stakes.

Answer:
It would take Northern dancer 2 minutes to run the Belmont stakes.

Explanation:
In the above-given question,
given that,
A horse named Northern Dancer won the Kentucky Derby with a time of exactly 2 minutes.
1.25/ 1.25/1 = 1 mile/1 minute.
the equivalent rate is 1.5/2.
so it would take Northern dancer 2 minutes to run the Belmont stakes.

Question 8.
If a cyclist rides at a constant rate of 24 miles per hour, how long would it take the cyclist to ride 156 miles?

Answer:
The long would it take the cyclist to ride 156 miles = 6.5 hours.

Explanation:
In the above-given question,
given that,
If a cyclist rides at a constant rate of 24 miles per hour.
156/24 = 6.5.
so the long would it take the cyclist to ride 156 miles = 6.5 hours.

Question 9.
The price of an 8-minute phone call is $1.20. What is the price of a 17-minute phone call?

Answer:
The price of a 17-minute phone call = 0.07.

Explanation:
In the above-given question,
given that,
The price of an 8-minute phone call is $1.20.
$1.20/8 = 0.15.
$1.20/17 = 0.07.
so the price of a 17-minute phone call = 0.07.

In 10 and 11, use the map at the right.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 94
The Garcia family is driving from Sacramento, California, to Key West, Florida. In 5 days, they have traveled 2,045 miles. At this rate, how long will it take them to travel from Sacramento to Key West?
Question 10.
How can you use rate reasoning to solve this problem? Explain.

Answer:
The rate will it take them to travel from Sacramento to Key West = 409.

Explanation:
In the above-given question,
given that,
The Garcia family is driving from Sacramento, California, to Key West, Florida.
In 5 days, they have traveled 2,045 miles.
2045/5 = 409.
so the rate will it take them to travel from Sacramento to Key West = 409.

Question 11.
Be Precise Show how to use numbers, units, and symbols precisely to solve the problem.
Answer:

Question 12.
Vik wrote the equation 470 • h = 3,008, where h is the number of hours it took a plane flying at a constant speed of 470 miles per hour to travel 3,008 miles. Solve for h.

Answer:
The number of miles per hour to travel 3008 miles = 6.4.

Explanation:
In the above-given question,
given that,
Vik wrote the equation 470 • h = 3,008,
470. h = 3008.
h = 3008/470.
h = 6.4.
so the number of miles per hour to travel 3008 miles = 6.4.

Question 13.
A nursery owner buys 7 panes of glass to fix some damage to his greenhouse. The 7 panes cost $15.05. Unfortunately, he breaks 2 more panes while repairing the damage. What is the cost of another 2 panes of glass?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 95

Answer:
The cost of another 2 panes of glass = $7.5.

Explanation:
In the above-given question,
given that,
A nursery owner buys 7 panes of glass to fix some damage to his greenhouse.
the 7 panes cost $15.05.
$15.05 / 7 = $2.15.
$15.05 / 2 = 7.525.
so the cost of another 2 panes of glass = $7.5.

Question 14.
Cheyenne drew a circle with diameter 1 meter. She measured the circumference to estimate the value of Pi. Complete the table, and then write an equation to find the circumference, C, for a circle with diameter d.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 96

Answer:
The circumference, C, for a circle with diameter d is 6.28, 9.42, and 12.56.

Explanation:
In the above-given question,
given that,
Cheyenne drew a circle with a diameter of 1 meter.
She measured the circumference to estimate the value of Pi.
3.14 x 1 = 3.14.
3.14 x 2 = 6.28.
3.14 x 3 = 9.42.
3.14 x 4 = 12.56.
so the circumference, c, for a circle with diameter d is 6.28, 9.42, and 12.56.

Question 15.
Jayden bought 70 feet of speaker wire for $18.20. He needs 30 more feet. If the unit price is the same, how much will Jayden pay for the extra 30 feet of wire? Explain.

Answer:
The much will Jayden pay for the extra 30 feet of wire = 0.60.

Explanation:
In the above-given question,
given that,
Jayden bought 70 feet of speaker wire for $18.20.
He needs 30 more feet.
$18.20/70 = 0.26.
$18.20/30 = 0.60.
so the much will Jayden pay for the extra 30 feet of wire = 0.60.

Question 16.
Higher Order Thinking Sasha runs at a constant speed of 3.8 meters per second for \(\frac{1}{2}\) hour. Then she walks at a constant rate of 1.5 meters per second for \(\frac{1}{2}\) hour. How far did Sasha run and walk in 60 minutes?

Answer:
The far did Sasha run and walk in 60 minutes = 30.

Explanation:
In the above-given question,
given that,
Sasha runs at a constant speed of 3.8 meters per second for \(\frac{1}{2}\) hour.
Then she walks at a constant rate of 1.5 meters per second for \(\frac{1}{2}\) hour.
3.8/ 0.5 = 7.6.
1.5 / 0.5 = 30.
so the far did Sasha run and walk in 60 minutes = 30.

Assessment Practice

Question 17.
Suppose that a leatherback turtle swam 7.5 kilometers in 3 hours at a constant speed.
PART A
How many kilometers per hour did the turtle swim?

Answer:
The turtle swim per hour = 2.5 miles.

Explanation:
In the above-given question,
given that,
leatherback turtle swam 7.5 kilometers in 3 hours.
7.5/3 = 2.5.
so the turtle swim per hour = 2.5 miles.

PART B
At this rate, how long would it take the turtle to swim 10 kilometers?

Answer:
The long would it take the turtle to swim 10 kilometers = 0.75.

Explanation:
In the above-given question,
given that,
the long would it take the turtle to swim 10 kilometers.
7.5/10 = 0.75.
so the long would it take the turtle to swim 10 kilometers = 0.75.

3-ACT MATH

3-Act Mathematical Modeling: Get in Line
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 97

ACT 1
Question 1.
After watching the video, what is the first question that comes to mind?
Answer:

Question 2.
Write the Main Question you will answer.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 98
Answer:

Question 3.
Construct Arguments Predict an answer to this Main Question. Explain your prediction.
Answer:

Question 4.
On the number line below, write a number that is too small to be the answer. Write a number that is too large.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 99
Answer:

Question 5.
Plot your prediction on the same number line.
Answer:

ACT 2
Question 6.
What information in this situation would be helpful to know? How would you use that information?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 100
Answer:

Question 7.
Use Appropriate Tools What tools can you use to solve the problem? Explain how you would use them strategically.
Answer:

Question 8.
Model with Math Represent the situation using mathematics. Use your representation to answer the Main Question.
Answer:

Question 9.
What is your answer to the Main Question? Is it higher or lower than your prediction? Explain why.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 111
Answer:

ACT 3
Question 10.
Write the answer you saw in the video.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 112
Answer:

Question 11.
Reasoning Does your answer match the answer in the video? If not, what are some reasons that would explain the difference?
Answer:

Question 12.
Make Sense and Persevere Would you change your model now that you know the answer? Explain.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 113
Answer:

Reflect
Question 13.
Model with Math Explain how you used a mathematical model to represent the situation. How did the model help you answer the Main Question?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 114
Answer:

Question 14.
Generalize Will your model work on other lights? Explain your reasoning.
Answer:

SEQUEL
Question 15.
Use Structure Later that week, it took between 20 and 21 minutes to get through the same light. How many cars were in line?
Answer:

Lesson 5.8 Ratio Reasoning: Convert Customary Units

Solve & Discuss It!
If 6.5 feet of snow were to fall in a 24-hour period, would the 1921 record be broken? There are 12 inches in 1 foot.
I can… use ratio reasoning to convert customary measurements.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 115

Reasoning
Use the relationship between inches and feet to solve the problem.

Focus on math practices
Make Sense and Persevere How many feet of snow would need to fall in Silver Lake, Colorado, to break the 1921 24-hour snowfall record from 1921?

Answer:
The record from 1921 is 3.15.

Explanation:
In the above-given question,
given that,
the number of feet of snow would need to fall in Silver Lake, Colorado, to break the 1921 24-hour snowfall record from 1921.
75.8 inches in 24 hours.
75.8/24 = 3.15.
so the record from 1921 is 3.15.

Essential Question
How can you use ratios to convert customary units of measure?

Try It!

According to city regulations, how many feet wide is the maximum sidewalk width? Explain.
Answer:

Convince Me! What conversion factor would you use when converting 66 inches to feet? Explain.

Try It!

Brandon is making bread. His recipe says to use 21 tablespoons of sugar. How many teaspoons of sugar should he use?

Answer:
The number of teaspoons of sugar should be used = 21 tablespoons.

Explanation:
In the above-given question,
given that,
Brandon is making bread.
His recipe says to use 21 tablespoons of sugar.
so the number of teaspoons of sugar should be used = 21 tablespoons.

Try It!

How many pounds does the elephant weigh?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 116

Answer:
The elephant weigh about 3.3 tons.

Explanation:
In the above-given question,
given that,
stella weighs approximately 3.3 tons.
so the weight of the elephant is 3.3 tons.

KEY CONCEPT
You can convert customary measures by finding an equivalent rate or by using dimensional analysis.
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 117
Use an equivalent rate.
1 mi = 5,280 ft
\(\frac{5,280 \mathrm{ft} \times 4.25}{1 \mathrm{mi} \times 4.25}=\frac{22,440 \mathrm{ft}}{4.25 \mathrm{mi}}\)

Use dimensional analysis.
4.25 m1 × \(\frac{5,280 \mathrm{ft}}{1 \mathrm{~m}}\)
= 4.25 × 5,280 ft
= 22,440 ft

Do You Understand?
Question 1.
Essential Question How can you use ratios to convert customary units of measure?

Answer:
We can find an equivalent rate by using dimensional analysis.

Explanation:
In the above-given question,
given that,
You can convert customary measures by finding an equivalent rate or by using dimensional analysis.
1 feet = 12 inches.
1 yard = 36 inches.
1 yard = 3 feet.
1 mile = 5280 feet.
1 mile = 1760 yards.
5280 – 1760 = 3520.
so we can find an equivalent rate by using dimensional analysis.

Question 2.
What is a conversion factor that relates miles to yards?

Answer:
The conversion factor that relates miles to yards is 5280 feet.

Explanation:
In the above-given question,
given that,
for example:
1 mile = 5280 feet.
1 mile = 1760 yards.
5280 – 1760 = 3520.
so the conversion factor that relates miles to yards is 5280 feet.

Question 3.
Construct Arguments Jenna used the conversion factor \(\frac{1 \mathrm{~T}}{2,000 \mathrm{lb}}\) to convert 50 tons to pounds. Did she use the correct conversion factor? Explain.

Answer:
Yes, she uses the correct conversion factor.

Explanation:
In the above-given question,
given that,
Jenna used the conversion factor \(\frac{1 \mathrm{~T}}{2,000 \mathrm{lb}}\) to convert 50 tons to pounds.
2000/50 = 40.
so she use the correct conversion factor.

Question 4.
How can you use the conversion rates of fluid ounces to cups, and cups to pints, to find the number of fluid ounces in a pint?
Answer:

Do You Know How?
Question 5.
Convert 27 inches to yards by finding an equivalent rate.

Answer:
The equivalent rate is 0.729.

Explanation:
In the above-given question,
given that,
1 inch = 0.027 yards.
27 x 0.027 = 0.729.
the equivalent rate is 0.729.

Question 6.
Use dimensional analysis to convert 1.8 pounds to ounces.

Answer:
1.8 pounds to ounces = 28.8 ounces.

Explanation:
In the above-given question,
given that,
1 pound = 16 ounces.
1.8 x 16 = 28.8 ounces.
so 1.8 pounds to ounces = 28.8 ounces.

Question 7.
Critique Reasoning Sam is tripling a recipe for an organic cleaning solution. The new recipe calls for 15 tsp of orange oil. To find how many tbsp this is, Sam converted this way:
Conversion factor: \(\frac{3 \text { tsp }}{1 \text { tbsp }}\)
\(15 t s p \times \frac{3 t s p}{1 \text { tbsp }}=\frac{45}{1} \text { tbsp }=45 \text { tbsp }\)
What error did Sam make?
Answer:

Practice & Problem Solving

In 8-13, complete each conversion.
Question 8.
5 pt = _______c

Answer:
5 pt = 10 cups.

Explanation:
In the above-given question,
given that,
5 us liquid cups = 10 us cups.
5 pt = 10 us cups.

Question 9.
2\(\frac{1}{2}\)gal = _________ qt

Answer:
2\(\frac{1}{2}\)gal = 10 qt.

Explanation:
In the above-given question,
given that,
a half of a gallon equal to 2 quarts.
2 + 2 + 2 + 2 + 2 = 10.
2\(\frac{1}{2}\)gal = 10 qt.

Question 10.
2,640 yd = ________ mi

Answer:
2640 yd = 1.5 miles.

Explanation:
In the above-given question,
given that,
1 yard = 0.000568 miles.
2640 yards = 1.5 miles.
so 2640 yds = 1.5 miles.

Question 11.
Convert 16 yards to feet. Use the conversion rate 3 feet = 1 yard.

Answer:
16 yards = 48 feet.

Explanation:
In the above-given question,
given that,
3 feet = 1 yard.
16 yards = 48 feet.
16 x 3 = 48.

Question 12.
Convert 10 pints to quarts. Use the conversion rate 1 quart = 2 pints.

Answer:
10 pints = 5 quarts.

Explanation:
In the above-given question,
given that,
1 quart = 2 pints.
10 us liquid pints = 5 us liquid quarts.
10 pints = 5 quarts.

Question 13.
Convert 12 ounces to pounds. Use the conversion rate 16 ounces = 1 pound.

Answer:
12 ounces = 0.75 pounds.

Explanation:
In the above-given question,
given that,
16 ounces = 1 pound.
12 ounces = 0.75 pounds.
so 12 ounces = 0.75 pounds.

Question 14.
Two neighbors in a rural area want to know the distance between their homes in miles. What should the neighbors use as a conversion factor to convert this distance to miles?
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 118

Answer:
The distance to miles is 0.8 miles.

Explanation:
In the above-given question,
given that,
Two neighbors in a rural area want to know the distance between their homes in miles.
4224 x 2 = 0.8 miles.
1 feet = 12 inches.
so the distance to miles is 0.8 miles.

Question 15.
A school custodian discovered a leak in a water pipe. The custodian found that 1,920 fluid ounces of water had leaked out. How many gallons of water is this? Use the conversion factor \(\frac{1 \text { gallon }}{128 \text { fluid ounces }}\).

Answer:
The conversion factor is 15 gallons.

Explanation:
In the above-given question,
given that,
A school custodian discovered a leak in a water pipe.
The custodian found that 1,920 fluid ounces of water had leaked out.
1920/128 = 15.
1920 us fluid ounces = 15 us liquid gallons.

Question 16.
Critique Reasoning Two students, Stella and Vladimir, complete the conversion statement 12 feet 8 inches = __________ inches.
Stella stated that 12 feet 8 inches = 152 inches. Vladimir stated that 12 feet 8 inches = 9 inches.
Which student is incorrect? Explain.

Answer:
Vladimir is incorrect.

Explanation:
In the above-given question,
given that,
12 feet 8 inches = 152 inches.
Vladimir is incorrect.
Stella is correct.

Question 17.
The hole for a support post needs to be 6 feet deep. It is currently 1 foot 8 inches deep. How much deeper must the hole be? Use the conversion factor \(\)
Envision Math Common Core Grade 6 Answer Key Topic 5 Understand And Use Ratio And Rate 119

Answer:
1 ft 8 in is 50.8 cm.

Explanation:
In the above-given question,
given that,
The hole for a support post needs to be 6 feet deep.
It is currently 1 foot 8 inches deep.
1 ft 8 in is 50.8 cm.

In 18 and 19, use the recipe card.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 120
Question 18.
Look for Relationships Cheryl has measured 3 cups of water. Is this enough water for Cheryl to make a double recipe of green slime for a class project? Explain.

Answer:

Explanation:
In the above-given question,
given that,
Cheryl has measured 3 cups of water.

Question 19.
There are 16 tablespoons in 1 cup. How many tablespoons of cornstarch would Cheryl need to make the green slime recipe 15 times?

Answer:
The tablespoons of cornstarch would Cheryl need to make = 92 cups.

Explanation:
In the above-given question,
given that,
There are 16 tablespoons in 1 cup.
tablespoons = 1 cup.
so the tablespoons of cornstarch would Cheryl need to make = 92 cups.

Question 20.
Make Sense and Persevere Len plans to run at least 3 miles each day to get ready for a cross-country race. One lap of the school track is 440 yards. If Len runs 10 laps each day, will he cover at least 3 miles? Explain.

Answer:
The Len runs 10 laps each day, will he cover at least 3 miles = 146.6.

Explanation:
In the above-given question,
given that,
Len plans to run at least 3 miles each day to get ready for a cross-country race.
One lap of the school track is 440 yards.
440/3 = 146.6.
so len runs 10 laps each day, will he cover at least 3 miles = 146.6.

Question 21.
Higher Order Thinking Hunter is splitting a quart of ice cream with 7 members of his family. If the quart is split evenly, how many cups will each family member get? Explain.

Answer:

Explanation:
In the above-given question,
given that,
Hunter is splitting a quart of ice cream with 7 members of his family.

Question 22.
A fully loaded and fueled space shuttle can weigh close to 4.5 million pounds at liftoff. What is this weight expressed in tons?
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 121
Answer:
The weight expressed in tons = 2250 us tons.

Explanation:
In the above-given question,
given that,
A fully loaded and fueled space shuttle can weigh close to 4.5 million pounds at liftoff.
weighs almost 4.5 million pounds.
the weight expressed in tons = 2250 us tons.

Assessment Practice

Question 23.
Select all the conversions that are true.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 122
☐ 18 ft = 6 yd
☐ 18 yd = 6 ft
☐ 0.5 mi = 10,560 ft
☐ 0.5 mi = 2,640 ft
☐ \(\frac{1}{2}\) mi = 880 yd

Answer:
18 ft = 6 yd.

Explanation:
In the above-given question,
given that,
1 ft = 12in.
1yd = 36 in.
6yd = 18 ft.
so 18 ft = 6 yd.

Lesson 5.9 Ratio Reasoning: Convert Metric Units

Solve & Discuss It!
Sam needs to fill a 5-liter water jug for his team. If Sam uses the water bottle to fill the jug, how many times does he
need to fill the water bottle to fill the jug?

I can… use unit rates to convert metric measurements.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 123

Reasoning
How many milliliters are in 5 liters?

Metric Units of Capacity
1,000 milliliters (ml) = 1 liter (L)
100 centiliters (CL) = 1 liter
10 deciliters (dL) = 1 liter
1 dekaliter (dal) = 10 liters
1 hectoliter (hL) = 100 liters
1 kiloliter (KL) = 1,000 liters

Focus on math practices
Be Precise How many liters of water does Sam’s water bottle hold when full?

Essential Question
How can you use ratios to convert metric units of measure?

Try It!

The middle of the skate ramp is 2.5 meters wide. Emelia and her father want to use a board that is 23.5 decimeters long. Is this board wide enough for them to use? Convert the decimeters to meters to explain.

Answer:
Yes, it is board-wide enough for them to use.

Explanation:
In the above-given question,
given that,
The middle of the skate ramp is 2.5 meters wide.
Emelia and her father want to use a board that is 23.5 decimeters long.
23.5 = 2.35 meters.
so it is board-wide enough for them to use.

Convince Me! How can you convert 2.5 meters to decimeters to determine whether the board is wide enough?

Try It!

To make violet paint, Iris mixes 0.25 liter of red paint, 0.25 liter of blue paint, and 4.5 centiliters of white paint. How many centiliters of paint are in the mixture?

Answer:
The number of centiliters of paint are in the mixture = 0.545 liters.

Explanation:
In the above-given question,
given that,
Iris mixes 0.25 liter of red paint, 0.25 liter of blue paint, and 4.5 centiliters of white paint.
4.5 centiliters = 0.045 litre.
0.045 + 0.25 + 0.25 = 0.545.
so the number of centiliters of paint are in the mixture = 0.545 liters.

KEY CONCEPT
You can convert metric measures by finding an equivalent rate or by using dimensional analysis.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 124
Use an equivalent rate.
1 kg = 1,000 g
\(\frac{1 \mathrm{~kg} \times 1.4}{1,000 \mathrm{~g} \times 1.4}=\frac{1.4 \mathrm{~kg}}{1,400 \mathrm{~g}}\)

Use dimensional analysis.
1.4 kg is equivalent to 1,400 g.
\(1.4 \mathrm{~kg} \times \frac{1,000 \mathrm{~g}}{1 \mathrm{~kg}}\)
= 1.4 × 1,000 g
= 1,400 g

Do You Understand?
Question 1.
Essential Question How can you use ratios to convert metric units of measure?

Answer:
We can convert metric measures by finding an equivalent rate or by using dimensional analysis.

Explanation:
In the above-given question,
given that,
1 kg = 1000 g.
1.4 kilogram is equivalent to 1400 g.
1.4 x 1000 = 1400 g.

Question 2.
Be Precise How are the metric units kilometer and kilogram the same? How are they different?

Answer:
The metrics units kilometers and kilogram are the same.

Explanation:
In the above-given question,
given that,
1 kg = 1000 g.
1.4 kilogram is equivalent to 1400 g.
1.4 x 1000 = 1400 g.

Question 3.
Reasoning Which is greater, 250 m or 0.25 km? Justify your reasoning.

Answer:
Both 250m or 0.25 km are the same.

Explanation:
In the above-given question,
given that,
250 meters = 0.25 kilometers.
divide the length value by 1000.
so both 250m or 0.25 km are the same.

Question 4.
How can you find the conversion rate for milliliters to kiloliters?

Answer:
The conversion rate for milliliters to kiloliters by 1000.

Explanation:
In the above-given question,
given that,
for example:
we can divide the length value by 1000.
1 ml = 1000 l.

Do You Know How?
Question 5.
What is the conversion factor when converting from liters to milliliters?
Answer:

Question 6.
Use an equivalent rate to convert 35 centimeters to meters.

Answer:
The equivalent rate to convert 35 centimeters to meters = 3500.

Explanation:
In the above-given question,
given that,
1 meter = 100 cm.
35 x 100 = 3500.
so the equivalent rate to convert 35 centimeters to meters = 3500.

Question 7.
Critique Reasoning Maddy wants to know how many centigrams are in 0.75 gram. She converted 0.75 gram to its equivalent in centigrams as shown. Is her work correct? Explain.
\(\frac{10 \mathrm{cg} \times 0.75}{1 \mathrm{~g} \times 0.75}=\frac{7.5 \mathrm{cg}}{0.75 \mathrm{~g}}\)
Answer:

Question 8.
Look at Exercise 7. Use dimensional analysis to convert 0.75 gram to centigrams.
Answer:

Practice & Problem Solving

Leveled Practice In 9 and 10, complete each conversion using an equivalent rate.
Question 9.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 125

Answer:
4m = 400 cm.

Explanation:
In the above-given question,
given that,
4m = 400 cm.
100 cm x 4/1m x 4m.
400cm/4m.

Question 10.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 126

Answer:
800 ml = 0.8 l.

Explanation:
In the above-given question,
given that,
800 ml = 0.8 liter.
(1000 ml/ 8)/ (1l/ 1000).
800 ml/ 1000l.
0.8 l.

Leveled Practice In 11 and 12, complete each conversion using dimensional analysis.
Question 11.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 127

Answer:
200 cl = 2 liters.

Explanation:
In the above-given question,
given that,
200 cl = 2 liters.
200 cl x 20000/100cl.
200/100 l.
2 l.

Question 12.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 128

Answer:
2.5 kg = 2500 grams.

Explanation:
In the above-given question,
given that,
2.5 kg x 1000g/1 kg.
250000/100 = 2500.
2.5 kg = 2500 grams.

In 13 and 14, complete each conversion.
Question 13.
80 cm = _______ m

Answer:
80 cm = 0.8m.

Explanation:
In the above-given question,
given that,
1m = 100 cm.
0.8m = 80 cm.
8 = 800 cm.

Question 14.
2.1 g = ________ mg

Answer:
2.1 g = 2100 mg.

Explanation:
In the above-given question,
given that,
2.1 g = 2100 milligrams.
1 kg = 1000 g.
2.1 g = 2100 mg.

In 15-17, use the table showing the amount of liquid that Whitney drinks each day.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 129
Question 15.
How many liters of water does Whitney drink each day?

Answer:
The number of liters of water does Whitney drinks each day = 1.5 l.

Explanation:
In the above-given question,
given that,
the amount of juice = 250 ml.
the amount of milk = 400 ml.
the amount of water = 1500 ml.
1 l = 1000 ml.
so the number of liters of water does Whitney drinks each day = 1.5 L.

Question 16.
What is the total amount of liquid, in liters, that Whitney drinks each day?

Answer:
The total amount of liquid in liters that Whitney drinks each day = 0.25 l.

Explanation:
In the above-given question,
given that,
the amount of juice = 250 ml.
the amount of milk = 400 ml.
the amount of water = 1500 ml.
1 l = 1000 ml.
so the total amount of liquid in liters that Whitney drinks each day = 0.25 L.

Question 17.
Troy drinks 1.8 L of water each day. How many more milliliters of water does Troy drink each day than Whitney?

Answer:
The more milliliters of water does Troy drink each day than Whitney = 300 ml.

Explanation:
In the above-given question,
given that,
Troy drinks 1.8 L of water each day.
1800 – 1500 = 300.
so the number of milliliters does Troy drink each day = 300 ml.

Question 18.
There are 10 millimeters in 1 centimeter, so about how many millimeters long is this dinosaur bone? Explain.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 130

Answer:
The number of milliliters long is the dinosaur bone = 220 ml.

Explanation:
In the above-given question,
given that,
There are 10 millimeters in 1 centimeter.
22 x 10 = 220 ml.
so the number of milliliters long is the dinosaur bone = 220 ml.

Question 19.
Critique Reasoning Savannah says that 1 kilogram is equivalent to 1,000,000 milligrams. Is Savannah correct? Explain.

Answer:
Yes, Savannah was correct.

Explanation:
In the above-given question,
given that,
Savannah says that 1 kilogram is equivalent to 1,000,000 milligrams.
1 kg = 1000 g.
1 g = 1000 mg.
1000 x 1000 = 1000000 mg.
so Savannah was correct.

Question 20.
Model with Math Lucas hiked 14,300 meters through the Everglades in the morning. After lunch, he continued hiking. When he finished the hike, he had covered 31.5 kilometers in all. Write an equation that can be used to find how far Lucas hiked after lunch.

Answer:
Lucas hiked after lunch = 453.96.

Explanation:
In the above-given question,
given that,
Lucas hiked 14,300 meters through the Everglades in the morning.
After lunch, he continued hiking.
When he finished the hike, he had covered 31.5 kilometers in all.
14300/31.5 = 453.96.
so Lucas hiked after lunch = 453.96.

Question 21.
Tariq has a collection of 35 quarters that he wants to send to his cousin. What is the total weight of the quarters in kilograms?
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 131

Answer:
The total weight of the quarters in kilograms = 6.17.

Explanation:
In the above-given question,
given that,
Tariq has a collection of 35 quarters that he wants to send to his cousin.
One quarter weighs 5.67 grams.
35/5.67 = 6.17.
so the total weight of the quarters in kilograms = 6.17.

Question 22.
Higher Order Thinking Louis has a bag of 25 pen shells. Each pen shell is 18 centimeters long. What is the combined length of the pen shells in meters?

Answer:
The combined length of the pen shells in meters = 450.

Explanation:
In the above-given question,
given that,
Louis has a bag of 25 pen shells.
Each pen shell is 18 centimeters long.
25 x 18 = 450.
so the combined length of the pen shells in meters = 450.

Assessment Practice

Question 23.
Select all the conversions that are equivalent to the capacity of a 5.5-liter pitcher of lemonade.
☐ 0.0055 kL
☐ 55 mL
☐ 0.055 kL
☐ 550 mL
☐ 5,500 ml

Answer:
Option A is correct.

Explanation:
In the above-given question,
given that,
5.5 liter = 5.5 x 1000.
0.0055.
so option A is correct.

Question 24.
Select all the conversions that are equivalent to the mass of a 425-gram football.
☐ 42,000 mg
☐ 42,500 cg
☐ 450 dg
☐ 4.25 hg
☐ 00.425 kg

Answer:

Explanation:
In the above-given question,
given that,
425 grams.

Lesson 5.10 Relate Customary and Metric Units

Explain It!
Gianna and her friends are in a relay race. They have a pail that holds 1 liter of water. They need to fill the 1-liter pail, run 50 yards, and dump the water into the large bucket until it overflows. Gianna says that as long as they do not spill any of the water, they will need 7 trips with the 1-liter pail before the large bucket overflows.

I can… convert between customary and metric units.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 132

A. Which conversion factor could you use to determine whether Gianna is correct? Explain.

Answer:
1 gal = 4 qt.

Explanation:
In the above-given question,
given that,
Gianna and her friends are in a relay race.
They have a pail that holds 1 liter of water.
1 gal is equal to 4 qt.
They need to fill the 1-liter pail, run 50 yards, and dump the water into the large bucket until it overflows.
1 gal = 4 qt.

B. Critique Reasoning Gianna’s friend Linus says that you cannot be certain how many trips it will take because the conversion is approximate. Is Linus’s reasoning appropriate? Explain.

Answer:
Yes, Gianna’s was correct.

Explanation:
In the above-given question,
given that,
Gianna and her friends are in a relay race.
They have a pail that holds 1 liter of water.
1 gal is equal to 4 qt.
They need to fill the 1-liter pail, run 50 yards, and dump the water into the large bucket until it overflows.
1 gal = 4 qt.

C. Construct Arguments Is Gianna correct that 7 trips are needed before the bucket overflows? If not, how many trips will it take? Use the table to justify your answer.
Answer:

Focus on math practices

Construct Arguments Morgan says that 4 liters is less than 1 gallon. Construct an argument to show that Morgan is incorrect.

Essential Question
How can you use ratios to convert customary and metric units of measure?

Try It!

Jacob is building a robot named T3-X that is 75 inches tall. To the nearest tenth, how many centimeters tall is T3-X?
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 133

Answer:
T3-x is 75 cm tall.

Explanation:
In the above-given question,
given that,
Jacob is building a robot named T3-X that is 75 inches tall.
1 in = 12 cm.
75in ( 1 cm/1 in).
75 x 1 cm = 75 cm.
T3-x is 75 cm tall.

Convince Me! If you want to find the height of T3-X in meters, will you get the same answer if you convert inches to centimeters, and then centimeters to meters, as you would if you convert inches to feet, and then feet to meters? Explain.

Try It!

Find the length of a 100-yard football field in meters. Use 1 yard = 3 feet and 1 meter ≈ 3.28 feet. Round to the nearest tenth.

Answer:
1 yard = 3 feet.
1 meter = 3.28 feet.

Explanation:
In the above-given question,
given that,
the length of a 100-yard football field meters.
1 yard = 3 feet.
1 meter = 3.28 feet.

KEY CONCEPT
You can use what you know about converting within one measurement system to relate customary and metric units. You can convert measures with customary and metric units by finding an equivalent rate or using dimensional analysis.
Use an equivalent rate.
1 kg ≈ 2.20 lb
\(\frac{1 \mathrm{~kg} \times 5}{2.20 \mathrm{lb} \times 5}=\frac{5 \mathrm{~kg}}{11 \mathrm{lb}}\)
5 kg ≈ 11 lb

Use dimensional analysis.
\(5 \mathrm{~kg} \times \frac{2.20 \mathrm{lb}}{1 \mathrm{~kg}}\)
5 × 2.20 = 11 lb
5 kg ≈ 11 lb

Do You Understand?
Question 1.
Essential Question How can you use ratios to convert customary and metric units of measure?
Answer:

Question 2.
Reasoning When converting centimeters to inches, do you multiply or divide by 2.54? Explain.
Answer:

Question 3.
Use Structure How can you find the approximate number of liters in 1 pint?
Remember: 1 quart = 2 pints
Answer:

Question 4.
How is the conversion from inches to centimeters different from other conversions between customary and metric units?
Answer:

Do You Know How?
In 5-8, find the equivalent measure. Round to the nearest tenth.
Question 5.
5 in. = _______ cm

Answer:
5 in = 12.7 cm.

Explanation:
In the above-given question,
given that,
1 ft = 12 in.
5 in = 12.7 cm.

Question 6.
2 mi ≈ _______ km

Answer:
2 mi = 3.219 km.

Explanation:
In the above-given question,
given that,
2 mi is equal to 3.129 km.
1 mi = 1.5645 km.
so 2 miles = 3.219 km.

Question 7.
113 g ≈ _______ oz

Answer:
113 g = 4 oz.

Explanation:
In the above-given question,
given that,
113 g is equal to 3.986 ounces.

Question 8.
14 kg ≈ ______ lb

Answer:
14 kg = 30 lb.

Explanation:
In the above-given question,
given that,
14 kg = 30.865 pounds.
pounds is equal to lb.
so 14 kg = 30 lb.

Question 9.
Convert 30 gallons to liters by finding an equivalent rate.
Answer:

Question 10.
Approximately how many ounces are equivalent to 1 kilogram?
Answer:

Practice & Problem Solving

In 11-18, find the equivalent measure. Round to the nearest tenth.
Question 11.
9qt ≈ _______ L

Answer:
9 qt = 8.52 l.

Explanation:
In the above-given question,
given that,
1 l = 1.06 qt.
9 qt = 8.52 l.

Question 12.
2 gal ≈ _______ L

Answer:
2 gal = 7.571 liters.

Explanation:
In the above-given question,
given that,
1 l = 0.264 gal.
2 gal = 7.571 liters.

Question 13.
2 in. ≈ _______ cm

Answer:
2 in = 5.08 cm.

Explanation:
In the above-given question,
given that,
3 in = 7.62 cm.
2 in = 5.08 cm.

Question 14.
5 km ≈ _______ mi

Answer:
5 km = 3.1 miles.

Explanation:
In the above-given question,
given that,
2 miles = 3.129 km.
5 km = 3.1 miles.

Question 14.
5 km ≈ ______ mi

Answer:
5 km = 3.1 mi.

Explanation:
In the above-given question,
given that,
5 km = 3.1 mi.

Question 15.
10 L ≈ ______ qt

Answer:
10 L = 10.567 q.

Explanation:
In the above-given question,
given that,
10 L = 10.567 q.
10.567 q = 10 L.

Question 16.
5.5 t ≈ ______ T

Answer:
5.5 t = 5.401 T.

Explanation:
In the above-given question,
given that,
5.5 t = 5.401.
1 tone = 0.982.
5.5 t = 5.401 T.

Question 17.
50 lb ≈ ______ kg

Answer:
50 lb = 23 kg.

Explanation:
In the above-given question,
given that,
lb is equal to pounds.
50 pounds = 22.68 kg.
50 lb = 23 kg.

Question 18.
10 oz ≈ ______ g

Answer:
10 oz = 283.495.

Explanation:
In the above-given question,
given that,
10 oz = 283.495 g.
283.495 g = 10 oz.

Question 19.
A chef at a restaurant uses 12 pounds of butter each day. About how many grams of butter does the chef use each day? Use the conversion factors \(\frac{16 \text { ounces }}{1 \text { pound }}\) and \(\frac{28.35 \text { grams }}{1 \text { ounce }}\)
Answer:

Question 20.
Reasoning Simone wants to know whether a new chest of drawers will fit next to her bed. The chest she would like to buy is 73 centimeters wide. She knows that her room is 86 inches wide. The bed is 76 inches wide. Will the chest fit next to her bed? Explain.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 134

Answer:
Yes, the chest fit next to her bed.

Explanation:
In the above-given question,
given that,
Simone wants to know whether a new chest of drawers will fit next to her bed.
The chest she would like to buy is 73 centimeters wide.
She knows that her room is 86 inches wide.
The bed is 76 inches wide.
so the chest fit next to her bed.

Question 21.
Be Precise Denali is the highest mountain in the United States. What is its height in meters? Round to the nearest whole number.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 135

Answer:

Explanation:
In the above-given question,
given that,
Denali is the highest mountain in the United States.
Denali is approximately 20,320 ft high.

Question 22.
Construct Arguments Francesca wants to convert 1 foot to centimeters. Use what you know about customary units to explain how she can do this.
Answer:

Question 23.
Higher Order Thinking At the state fair, a person must be at least 138 centimeters tall to ride the roller coaster. Billy wants to ride the coaster. He is 4 feet 7 inches tall. Is Billy tall enough to ride the coaster? Explain.
Answer:

Question 24.
Paul’s car holds a maximum of 19 gallons of gas. About how many liters of gas does Paul need to fill his gas tank?
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 136
Answer:
The number of liters of gas does Paul need to fill his gas tank = 10 liters.

Explanation:
In the above-given question,
given that,
Paul’s car holds a maximum of 19 gallons of gas.
9 gallons is remaining as shown.
19 – 9 = 10.
so the number of liters of gas does paul need to fill his gas tank = 10 liters.

Assessment Practice

Question 25.
The posted speed limit is 65 miles per hour. Select all the metric measures that are faster than 65 miles per hour.
☐ 65 km per hour
☐ 97.5 km per hour
☐ 104 km per hour
☐ 105.7 km per hour
☐ 120.3 km per hour

Answer:
Option A is correct.

Explanation:
In the above-given question,
given that,
The posted speed limit is 65 miles per hour.
65 km per hour.
so option A is correct.

Question 26.
Boys competing in the long jump event must jump at least 15 feet to qualify for the state track and field meet. Select all the metric measures that are less than 15 feet.
☐ 6.5 m
☐ 5.0 m
☐ 4.5 m
☐ 3.92 m
☐ 3.5 m

Answer:

Topic 5 Review

Essential Question
What are ratios and rates? How can you use ratios and rates to describe quantities and solve problems?

Vocabulary Review
Complete each definition and then provide an example of each vocabulary word.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 137

Use Vocabulary in Writing
Explain how you can convert 52 ounces to pounds. Use vocabulary words in your explanation.

Concepts and Skills Review

Lesson 5.1 Understand Ratios

Quick Review
A ratio is a relationship in which for every x units of one quantity there are y units of another quantity. A ratio can be written using the word “to,” a colon, or a fraction bar to separate the two terms.

Example
The ratio of men to women at a small wedding is 6:4. If there are 16 women at the wedding, how many men are at the wedding?
Draw a diagram to represent the ratio. Because 4 boxes represent 16 women, each box represents 4 women.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 138
There are 24 men at the wedding.

Practice
A florist uses 5 red roses for every 2 white roses in her bouquets.
Question 1.
Write the ratio of white roses to red roses in three different ways.

Answer:
The ratio of white roses to red roses is 2:5.

Explanation:
In the above-given question,
given that,
A florist uses 5 red roses for every 2 white roses in her bouquets.
the ratio of white roses to red roses is 2:5.
so the ratio is 2:5.

Question 2.
Write the ratio of red roses to the total number of flowers in three different ways.

Answer:
The ratio of red roses to the total number of flowers is 5:7.

Explanation:
In the above-given question,
given that,
A florist uses 5 red roses for every 2 white roses in her bouquets.
the ratio of red roses to the total number of flowers is 5:7.
so the ratio is 5:7.

Question 3.
If the florist uses 10 red roses in a bouquet, how many white roses does she use?

Answer:
The ratio is 10:4.

Explanation:
In the above-given question,
given that,
A florist uses 5 red roses for every 2 white roses in her bouquets.
if the florist uses 10 red roses in a bouquet.
he can use 4 white roses.
10: 4.
5:2.
so the ratio is 10:4.

Question 4.
If the florist uses 10 white roses in an arrangement, how many red roses does she use?

Answer:
The ratio is 25:10

Explanation:
In the above-given question,
given that,
A florist uses 5 red roses for every 2 white roses in her bouquets.
if the florist uses 10 white roses in an arrangement.
he can use 25 red roses.
25:10.
5:2.
so the ratio is 25:10.

Lesson 5.2 Generate Equivalent Ratios

Quick Review
You can multiply or divide both terms of a ratio by the same nonzero number to find equivalent ratios.

Example
Find two ratios that are equivalent to \(\frac{21}{126}\)
One Way
Multiply.
\(\frac{21 \times 2}{126 \times 2}=\frac{42}{252}\)

Another Way
Divide.
\(\frac{21 \div 3}{126 \div 3}=\frac{7}{42}\)

Practice
In 1-4, find two ratios equivalent to the given ratio.
Question 1.
\(\frac{5}{12}\)

Answer:
The ratios are 10/24 and 1/2.4.

Explanation:
In the above-given question,
given that,
the ratio is 5/12.
5 x 2 = 10.
12 x 2 = 24.
the ratio is 10/24.
divide by 5.
5/5 = 1.
12/5 = 2.4.
so the ratio is 1/2.4

Question 2.
14:32

Answer:
The ratios are 7/16 and 5/12.

Explanation:
In the above-given question,
given that,
the ratio is 14/32.
7 x 2 = 14.
16 x 2 = 32.
the ratio is 7/16.
divide by 2.
10/2 = 5.
24/2 = 12.
so the ratio is 5/12.

Question 3.
3 to 4

Answer:
The ratios are 6/8 and 1/1.3.

Explanation:
In the above-given question,
given that,
the ratio is 3/4.
3 x 2 = 6.
4 x 2 = 8.
the ratio is 6/8.
divide by 3.
3/3 = 1.
4/3 = 1.3.
so the ratio is 1/1.3.

Question 4.
\(\frac{7}{8}\)

Answer:
The ratios are 14/16 and 1/1.14.

Explanation:
In the above-given question,
given that,
the ratio is 7/8.
7 x 2 = 14.
8 x 2 = 16.
the ratio is 14/16.
divide by 7.
7/7 = 1.
8/7 = 1.14.
so the ratio is 1/1.14.

Question 5.
For every 4 bagels sold at a bakery, 7 muffins are sold. How many muffins are sold when the bakery sells 24 bagels? Complete the table.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 139

Answer:
The missing values are 14, 21, 28, 35, and 42.

Explanation:
In the above-given question,
given that,
For every 4 bagels sold at a bakery, 7 muffins are sold.
the ratio is 1:2.
4 x 1 = 4, 4 x 2 = 8, 4 x 3 = 12, 4 x 4 = 16, 4 x 5 = 20, and 4 x 6 = 24.
7 x 1 = 7, 7 x 2 = 14, 7 x 3 = 21, 7 x 4 = 28, 7 x 5 = 35, and 7 x 6 = 42.
so the missing values are 14, 21, 28, 35, and 42.

Lesson 5.3 Compare Ratios

Quick Review
To compare ratios, make a table to show each ratio and then find a value in which one of the terms is the same in both tables.

Example
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 140
Erica can complete more facts than Klayton.

Answer:
The missing value is 4.

Explanation:
In the above-given question,
given that,
the number of days is 1, 2, 3, and 4.
the days of the sun are 2, 4, 6, and 8.
2 x 1 = 2.
2 x 2 = 4.
2 x 3 = 6.
2 x 4 = 8.
so the missing value is 4.

Practice
Question 1.
The school soccer team buys 3 soccer balls for every 2 players. The school volleyball team buys 7 volleyballs for every 5 players. Which team buys more balls per player?

Answer:
The team buys more balls per player = 6:35.

Explanation:
In the above-given question,
given that,
The school soccer team buys 3 soccer balls for every 2 players.
The school volleyball team buys 7 volleyballs for every 5 players.
3 x 2 = 6.
7 x 5 = 35.
so the team buys more balls per player = 6:35.

Question 2.
Jenna walks 12 miles in 5 days. Alex walks 7 miles in 3 days. Who walks more miles per day?

Answer:
The ratio is 60/21.

Explanation:
In the above-given question,
given that,
Jenna walks 12 miles in 5 days. Alex walks 7 miles in 3 days.
12 x 5 = 60.
7 x 3 = 21.
so the ratio is 60/21.

Lesson 5.4 Represent and Graph Ratios

Quick Review
You can solve some ratio problems by making a table of equivalent ratios and then graphing the pairs of values on a coordinate plane.

Example
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 140
There will be 4 rainy days if there are 8 sunny days.

Practice
Question 1.
In gym class, the sixth graders walk 2 laps for every 3 laps they run. If the students run 12 laps, how many laps will they walk? Complete the table. Then plot the pairs of values on the coordinate plane.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 141

Answer:
The missing values are 4, 6, and 8.

Explanation:
In the above-given question,
given that,
In gym class, the sixth graders walk 2 laps for every 3 laps they run.
the run laps on the y-axis.
the walk laps on the x-axis.
3 x 2 = 6, 3 x 3 = 9, 3 x 4 = 12.
2 x 2 = 4, 2 x 3 = 6, 2 x 4 = 8.

Lesson 5.5 Understand Rates and Unit Rates

Quick Review
A rate is a ratio that relates two quantities with different units. A unit rate relates a quantity to 1 unit of another quantity. You can use what you know about dividing fractions to write a ratio of fractions as a unit rate.

Example
Write 20 meters in 4 minutes as a rate and as a unit rate.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 142

Practice
Write each statement as a unit rate.
Question 1.
78 miles on 3 gallons

Answer:
The unit rate is 26/1.

Explanation:
In the above-given question,
given that,
78 miles on 3 gallons.
unit rate is 78/3.
3 x 1 = 3.
3 x 26 = 78.
so the unit rate is 26/1.

Question 2.
18 laps in 6 minutes

Answer:
The unit rate is 18.

Explanation:
In the above-given question,
given that,
18 laps in 6 minutes
unit rate is 18/6.
6 x 1 = 6.
3 x 6 = 18.
so the unit rate is 18/1.

Question 3.
48 sandwiches for 16 people

Answer:
The unit rate is 3.

Explanation:
In the above-given question,
given that,
48 sandwiches for 16 people.
unit rate is 48/16.
16 x 1 = 16.
3 x 16 = 48.
so the unit rate is 3.

Question 4.
49 houses in 7 blocks

Answer:
The unit rate is 7.

Explanation:
In the above-given question,
given that,
49 houses in 7 blocks.
unit rate is 49/7.
7 x 1 = 7.
7 x 7 = 49.
so the unit rate is 7.

Question 5.
6 desks in 2 rows

Answer:
The unit rate is 3.

Explanation:
In the above-given question,
given that,
6 desks in 2 rows.
unit rate is 6/2.
2 x 1 = 2.
3 x 2 = 6.
so the unit rate is 3.

Lesson 5.6 Compare Unit Rates

Quick Review
A unit rate compares a quantity to 1 unit of another quantity. To compare unit rates, compare the first terms.

Example
On Pet Day, Meg’s turtle crawled 30 feet in 6 minutes, and Pat’s turtle crawled 25 feet in 5 minutes. Whose turtle crawled at a faster rate?
Write each rate.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 143
Both turtles crawled at the same rate.

Practice
Question 1.
Which is the better value? Circle it.
$5.00 for 4 mangoes
$6.00 for 5 mangoes

Answer:
Both have the same value.

Explanation:
In the above-given question,
given that,
$5.00 for 4 mangoes
$6.00 for 5 mangoes
$5/4 = 1.25.
$6/5 = 1.2.
so both of the values are the same.

Question 2.
Who earned more each month? Circle it.
Atif: $84 over 3 months
Jafar: $100 over 4 months

Answer:
Atif earned more than Jafar.

Explanation:
In the above-given question,
given that,
Atif: $84 over 3 months
Jafar: $100 over 4 months
84/3 = 28.
100/4 = 25.
so Atif earned more.

Question 3.
Which is a faster rate? Circle it.
3 laps in 5 minutes
4 laps in 7 minutes

Answer:
3 laps in 5 minutes is the faster rate.

Explanation:
In the above-given question,
given that,
3 laps in 5 minutes
4 laps in 7 minutes
3/5 = 0.6.
4/7 = 0.5.
option A is correct.

Question 4.
Which is the better value? Circle it.
3 sandwiches for $15.00
4 sandwiches for $21.00

Answer:
3 sandwiches for $15.00.

Explanation:
In the above-given question,
given that,
3 sandwiches for $15.00
4 sandwiches for $21.00
3/15 = 1/5.
1/5 = 0.2.
4/21 = 0.1.

Question 5.
Which is the greater rate? Circle it.
6 points in 3 attempts
15 points in 5 attempts

Answer:
15 points in 5 attempts.

Explanation:
In the above-given question,
given that,
6 points in 3 attempts
15 points in 5 attempts
6/3 = 2.
15/5 = 3.
15 points in 5 attempts.

Lesson 5.7 Solve Unit Rate Problems

Quick Review
You can use a ratio table or a unit rate to solve problems involving ratios or rates.

Example
A plane travels at a rate of 780 miles in 2 hours. At this rate, how far will it travel in 3.5 hours?
Find the unit rate
\(\frac{780 \text { miles } \div 2}{2 \text { hours } \div 2}=\frac{390 \text { miles }}{1 \text { hour }}\)

Find an equivalent rate.
\(\frac{390 \text { miles } \times 3.5}{1 \text { hour } \times 3.5}=\frac{1,365 \text { miles }}{3.5 \text { hours }}\)
The plane will travel 1,365 miles in 3.5 hours.

Practice
Question 1.
Doug has 5 hours to make an on-time delivery 273 miles away. Doug drives at a constant speed of 55 miles per hour. Will Doug make the delivery by the deadline? Explain.

Answer:
Yes, Doug makes the delivery by the deadline.

Explanation:
In the above-given question,
given that,
Doug has 5 hours to make an on-time delivery 273 miles away.
Doug drives at a constant speed of 55 miles per hour.
273/5 = 54.6.
54.6 x 55 = 3003.
Yes, Doug makes the delivery by the deadline.

Question 2.
Marie has 8 hours to write a 45-page chapter for her book. Marie writes at a constant speed of 4 pages per hour. Will Marie complete the chapter in time? Explain.

Answer:
Marie takes 90 hours to complete.

Explanation:
In the above-given question,
given that,
Marie has 8 hours to write a 45-page chapter for her book.
Marie writes at a constant speed of 4 pages per hour.
45 x 8 = 360.
360 /4 = 90.

Lesson 5.8 Ratio Reasoning: Convert Customary Units

Quick Review
You can convert customary measures by finding equivalent rates or by using dimensional analysis.

Example
How many pints are equivalent to 4 quarts?
Find an equivalent rate:
2 pints = 1 quart …….. Identify the conversion rate.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 144
So, 8 pints are equivalent to 4 quarts.

Practice
In 1-4, complete each conversion.
Question 1.
2 mi = _______ ft

Answer:
2 miles = 10560 feet.

Explanation:
In the above-given question,
given that,
1 mile = 63360 in.
1 ft = 12 in.
2 mi = 63360 x 2.
126720/2 = 10560.

Question 2.
144 in. = _______ yd

Answer:
144 in = 4.0032 yd.

Explanation:
In the above-given question,
given that,
1 inch = 0.0278 yd.
144 x 0.0278.
4.0032.
144 in = 4.0032 yd.

Question 3.
4 oz = _______ lb

Answer:
4 oz = 0.0625 lb.

Explanation:
In the above-given question,
given that,
1 oz = 0.0625 lb.
4 oz = 4 x 0.0625.
0.25 lb.

Question 4.
3 gal = _______ qt

Answer:
3 gal = 12 qt.

Explanation:
In the above-given question,
given that,
1 gal = 4 us qt.
3 gal = 3 x 4.
3 gal = 12 qt.

Question 5.
The hippo at the zoo weighs 1.5 tons. How many pounds does the hippo weigh?

Answer:
The weight of the hippo is 3000 pounds.

Explanation:
In the above-given question,
given that,
The hippo at the zoo weighs 1.5 tons.
1 ton = 2000 pounds.
1.5 tons = 1.5 x 2000.
3000.
The weight of the hippo is 3000 pounds.

Lesson 5.9 Ratio Reasoning: Convert Metric Units

Quick Review
To convert metric units, use the same methods used for converting customary units. Either use the conversion rate to find an equivalent rate or use dimensional analysis.

Example
Tariq rode his bike 15,100 meters. How many kilometers did he ride his bike?
Find an equivalent rate:
1,000 meters = 1 kilometer
\(\frac{1,000 m \times 15.1}{1 \mathrm{~km} \times 15.1}=\frac{15,100 \mathrm{~m}}{15.1 \mathrm{~km}}\)
Use dimensional analysis:
\(15,100 \mathrm{~m} \times \frac{1 \mathrm{~km}}{1,000 \mathrm{~m} }=\frac{15,100}{1,000} \mathrm{~km}=15.1 \mathrm{~km}\)
Tariq rode 15.1 kilometers.

Practice
In 1-4, complete each conversion.
Question 1.
3 m = _______ mm

Answer:
3m = 3000 mm.

Explanation:
In the above-given question,
given that,
1 m = 1000 mm.
3 m = 3 x 1000.
3m = 3000 mm.

Question 2.
3,520 mm = _______ cm

Answer:
3520 mm = 352 cm.

Explanation:
In the above-given question,
given that,
1mm = 0.1 cm.
3520 mm = 352 cm.

Question 3.
4.2 kg = _______ g

Answer:
4.2 kg = 4200 g.

Explanation:
In the above-given question,
given that,
1 kg = 1000 g.
4.2 kg = 4.2 x 1000.
4.2 x 1000 = 4200 g.
4.2 kg = 4200 g.

Question 4.
300 mL = _______ L

Answer:
300 ml = 0.3 l.

Explanation:
In the above-given question,
given that,
1ml = 0.001 l.
300 ml = 300 x 0.001.
300 x 0.001 = 0.3 l.
300 ml = 0.3l.

Question 5.
Li needs to buy 2 kilograms of apples. If she buys 9 apples that each weigh approximately 150 grams, will she have enough? Explain.

Answer:
Yes, she has enough.

Explanation:
In the above-given question,
given that,
Li needs to buy 2 kilograms of apples.
If she buys 9 apples that each weigh approximately 150 grams.
150 x 9 = 1350 g.
2 kg = 2000 g.
so she has enough space.

Lesson 5.10 Relate Customary and Metric Units

Quick Review
To convert between metric and customary units, use the conversion rate and find an equivalent rate, or use dimensional analysis. Most conversions will be approximate because, except in the case of inches to centimeters, the conversion rates are approximate.

Example
Gwen has a cooler that holds 3 quarts. About how many liters does the cooler hold?
1 qt ≈ 0.95 L
3 qt × \(\frac{0.95 \mathrm{~L}}{1 \mathrm{~qt}}\) = (3 × 0.95) L = 2.85 L
Gwen’s cooler holds approximately 2.85 liters.

Practice
In 1-4, find the equivalent measure. Round to the nearest tenth.
Question 1.
100 g ≈ ________ oz

Answer:
100 g = 15372.2 oz.

Explanation:
In the above-given question,
given that,
1 gal = 153.722 oz.
100 g = 153.722 x 100.
15372.2.

Question 2.
6 ft ≈ _______ m

Answer:
6 ft = 1.83 m.

Explanation:
In the above-given question,
given that,
1 ft = 0.305 m.
6 ft = 6 x 0.305.
6 x 0.305 = 1.83.
6 ft = 1.83 m.

Question 3.
57 gal ≈ _______ L

Answer:
57 gal = 256.5 l.

Explanation:
In the above-given question,
given that,
1 gal = 4.5 l.
57 gal = 57 x 4.5.
57 x 4.5 = 256.5.
57 gal = 256.5 l.

Question 4.
27 km ≈ _______ mi

Answer:
27 km = 16.767 mi.

Explanation:
In the above-given question,
given that,
1 km = 0.621 mi.
27 km = 27 x 0.621.
27 x 0.621 = 16.767.
27 km = 16.767 mi.

Question 5.
The science class is raising monarch caterpillars. One of the caterpillars weighs 2.3 ounces. About how many grams does the caterpillar weigh? Round to the nearest tenth.

Answer:
The caterpillar weighs 65.2 grams.

Explanation:
In the above-given question,
given that,
The science class is raising monarch caterpillars.
One of the caterpillars weighs 2.3 ounces.
1 ounce = 28.35 grams.
2.3 x 28.35 = 65.205.
so the caterpillar weighs 65.2 grams.

Topic 5 Fluency Practice

Pathfinder
Shade a path from START to FINISH. Follow the sums and differences in which the digit in the ones place is greater than the digit in the tenths place. You can only move up, down, right, or left.
I can… add and subtract multidigit decimals.
Envision Math Common Core Grade 6 Answers Topic 5 Understand And Use Ratio And Rate 145

enVision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions

enVision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions

Go through the enVision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions regularly and improve your accuracy in solving questions.

enVision Math Common Core 5th Grade Answers Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions

Use Equivalent Fractions to Add and Subtract Fractions

Essential Questions: How can sums and differences of fractions and mixed numbers be estimated? What are common procedures for adding and subtracting fractions and mixed numbers?

Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 1
enVision STEM Project: Fossils Tell Story

Do Research Use the Internet or other sources to find out more about fossils. What are fossils? How and where do we find them? What do they tell us about the past? What can they tell us about the future? Pay particular attention to fossils from the Eocene epoch.

Journal: Write a Report Include what you found. Also in your report:
• Describe a fossil that you have seen or would like to find.
• Tell if there are any fossils where you live.
• Make up and solve addition and subtraction problems about fossils. Use fractions and mixed numbers in your problems.

Review What You Know

Choose the best term from the box. Write it on the blank.

Vocabulary

• denominator
• numerator
• unit fraction
• fraction
• mixed number

Question 1.
A ___ has a whole number part and a fraction part.
Answer:
A Mixed Number has a whole number part and a fraction part.

Question 2.
A ___ represents the number of equal parts in one whole.
Answer:
A Denominator represents the number of equal parts in one whole

Use Equivalent Fractions to Add and Subtract Fractions 1

Question 3.
A ___ has a numerator of 1.
Answer:
A Unit Fraction has a numerator of 1.

Question 4.
A symbol used to name one or more parts of a whole or a set, or a location on the number line, is a ____.
Answer:
A symbol used to name one or more parts of a whole or a set, or a location on the number line, is a Fraction.

Compare Fractions
Compare. Write >, <, or = for each Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6.

Question 5.
\(\frac{1}{5}\) Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6 \(\frac{1}{15}\)
Answer:
\(\frac{1}{5}\) Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-6 \(\frac{1}{15}\)

Question 6.
\(\frac{17}{10}\) Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6 \(\frac{17}{5}\)
Answer:
\(\frac{17}{10}\) Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-6 \(\frac{17}{5}\)

Question 7.
\(\frac{5}{25}\) Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6 \(\frac{2}{5}\)
Answer:
\(\frac{5}{25}\) Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-6 \(\frac{2}{5}\)

Question 8.
\(\frac{12}{27}\) Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6 \(\frac{6}{9}\)
Answer:
\(\frac{12}{27}\) Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-6 \(\frac{6}{9}\)

Question 9.
\(\frac{11}{16}\) Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6 \(\frac{2}{8}\)
Answer:
\(\frac{11}{16}\) Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-6 \(\frac{2}{8}\)

Question 10.
\(\frac{2}{7}\) Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 6 \(\frac{1}{5}\)
Answer:
\(\frac{2}{7}\) Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-6 \(\frac{1}{5}\)

Question 11.
Liam bought \(\frac{5}{8}\) pound of cherries. Harrison bought more cherries than Liam. Which could be the amount of cherries that Harrison bought?
A. \(\frac{1}{2}\) pound
B. \(\frac{2}{5}\) pound
C. \(\frac{2}{3}\) pound
D. \(\frac{3}{5}\) pound
Answer:
D. \(\frac{3}{5}\) pound

Question 12.
Jamie has read \(\frac{1}{4}\) of a book. Raul has read of the same book. Who is closer to reading the whole book? Explain.
Answer:  Jamie and Raul are in the same position to complete the book because Jamie has read \(\frac{1}{4}\) of a book and also Raul has read \(\frac{1}{4}\) of a book. They both completed the same book with same amount. Both are equal.

Equivalent Fractions
Write a fraction equivalent to each fraction.

Question 13.
\(\frac{6}{18}\)
Answer:
\(\frac{6}{18}\) x 2 = \(\frac{12}{32}\)

Use Equivalent Fractions to Add and Subtract Fractions 2

Question 14.
\(\frac{12}{22}\)
Answer:
\(\frac{12}{22}\) x 2 = \(\frac{24}{44}\)

Question 15.
\(\frac{15}{25}\)
Answer:
\(\frac{15}{25}\) x 2 = \(\frac{30}{50}\)

Question 16.
\(\frac{8}{26}\)
Answer:
\(\frac{8}{26}\) x 2 = \(\frac{16}{52}\)

Question 17.
\(\frac{14}{35}\)
Answer:
\(\frac{14}{35}\) x 2 = \(\frac{28}{70}\)

Question 18.
\(\frac{4}{18}\)
Answer:
\(\frac{4}{18}\) x 2 = \(\frac{8}{36}\)

Question 19.
\(\frac{1}{7}\)
Answer:
\(\frac{1}{7}\) x 2 = \(\frac{1}{14}\)

Question 20.
\(\frac{4}{11}\)
Answer:
\(\frac{4}{11}\) x 2 = \(\frac{8}{22}\)

Pick a Project

PROJECT 7A
What’s in your gumbo?
Project: Record a Cooking Show
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.2

PROJECT 7B
Does this story sound fishy?
Project: Write a Tall Tale about Fishing Friends
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.3

PROJECT 7C
How many cups of juice can you get from 5 oranges?
Project: Get the Juice from Oranges
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.4

3-ACT MATH PREVIEW

Math Modeling

The Gif Recipe

Before watching the video, think: Some recipes are easier to follow than others. I’ve never made this one before. Maybe I should read the entire recipe before starting to cook.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.5

Lesson 7.1 Estimate Sums and Differences of Fractions

Activity

Solve&Share
Jack needs about 1\(\frac{1}{2}\) yards of string. He has three pieces of string that are different lengths. Without finding the exact amount, which two pieces should he choose to get closest to 1\(\frac{1}{2}\) yards of string? Solve this problem any way you choose.

Reasoning You can use number sense to estimate the answer. Show your work!
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.6
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-16.6

Look Back! How can a number line help you estimate?
Answer: It helps me to estimate the appropriate answer. It makes easy to add the yards and easy to find the yards which are closet to the given yard. It is somewhat in a elaborate way.

Use Equivalent Fractions to Add and Subtract Fractions 3

Visual Learning Bridge

Essential Question How Can You Estimate the Sum of Two Fractions?

A.
Mr. Fish is welding together two copper pipes to repair a leak. He will use the pipes shown. Is the new pipe closer to \(\frac{1}{2}\) foot or 1 foot long? Explain.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.8

B.
Step 1
Replace each fraction with the nearest half or whole. A number line can make it easy to decide if each fraction is closest to 0, \(\frac{1}{2}\), or 1.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 17.1
\(\frac{1}{6}\) is between 0 and 2, but is closer to 0.
\(\frac{5}{12}\) is also between 0 and 2, but is closer to the benchmark fraction \(\frac{1}{2}\).

C.
Step 2
Add to find the estimate.
A good estimate of \(\frac{1}{6}\) + \(\frac{5}{12}\) is 0 + \(\frac{1}{2}\), or \(\frac{1}{2}\). So, the welded pipes will be closer to 2 foot than 1 foot long

Since each addend is less than 5, it is reasonable that their sum is less than 1.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 17.2

Convince Me! Critique Reasoning Nolini says that if the denominator is more than twice the numerator, the fraction can always be replaced with 0. Is she correct? Give an example in your explanation.
Answer: Yes,
It depends on how accurate you want your answer to be, but basically yes, imagine we set our numerator to be x, and our denominator to be 2x, if we built our fraction we will get that:  If the denominator of a fraction is exactly twice the numerator, then the fraction will be simplified to 1/2 or 0.5.Now, the greater the denominator is, the closer the fraction will get to zero.
Take for example I had an fraction like this:

which approximates to 0. If we made the denominator bigger, let’s say 7, we would get: 
notice the answer is closer to 0 this time, so it’s valid to round it to zero. If we made the denominator greater, let’s say 25, we would get: and so on. So it is true that if the denominator of a fraction is greater than twice the numerator, we can always replace the fraction with a 0
(depending on how accurate you want your answer to be).

Guided Practice

Do You Understand?

Question 1.
In the problem at the top of page 270, would you get the same estimate if Mr. Fish’s pipes measured foot and \(\frac{7}{12}\) foot?
Answer:
Yes, The estimation would be the same because Mr. Fish’s pipes measured foot is \(\frac{1}{6}\) + \(\frac{5}{12}\) = 0.5 and the \(\frac{7}{12}\) = 0.5

Question 2.
Number Sense If a fraction has a 1 in the numerator and a number greater than 2 in the denominator, will the fraction be closer to 0, \(\frac{1}{2}\), or 1? Explain.
Answer:
If a fraction has a 1 in the numerator and a number greater than 2 in the denominator, will the fraction be closer to \(\frac{1}{2}\) because the numerator is 1 and the denominator is 2 that means \(\frac{1}{2}\) = 0.5

Do You Know How?

In 3 and 4, use a number line to tell if each fraction is closest to 0, \(\frac{1}{2}\), or 1. Then estimate the sum or difference.

Question 3.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 18
a. \(\frac{11}{12}\) Closest to: ___
b. \(\frac{1}{6}\) Closest to: _____
Estimate the sum \(\frac{11}{12}\) + \(\frac{1}{6}\)
c. 1 + __ = __
Answer:
a. \(\frac{11}{12}\) Closest to: 1
b. \(\frac{1}{6}\) Closest to:  \(\frac{1}{2}\)
Estimate the sum \(\frac{11}{12}\) + \(\frac{1}{6}\)
c. 1 +\(\frac{1}{2}\) = 1.5

Question 4.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 19
a. \(\frac{14}{16}\) Closest to: ___
b. \(\frac{5}{8}\) Closest to: ___
Estimate the difference \(\frac{14}{16}\) – \(\frac{5}{8}\).
c. ___ – ___ = ___
Answer:
a. \(\frac{14}{16}\) Closest to: 1
b. \(\frac{5}{8}\) Closest to:  \(\frac{1}{2}\)
Estimate the difference \(\frac{14}{16}\) – \(\frac{5}{8}\).
c. 1 – \(\frac{1}{2}\) = 0.5

Independent Practice

Leveled Practice In 5, use a number line to tell if each fraction is closest to 0, \(\frac{1}{2}\), or 1
In 6-11, estimate the sum or difference by replacing each fraction with 0, \(\frac{1}{2}\), or 1.

Use Equivalent Fractions to Add and Subtract Fractions 4

Question 5.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 20
a. \(\frac{7}{8}\) Closest to: ____
b. \(\frac{5}{12}\) Closest to: ___
Estimate the difference \(\frac{7}{8}\) – \(\frac{5}{12}\)
c. ___ – ___ = ___
Answer:
a. \(\frac{7}{8}\) Closest to: 1
b. \(\frac{5}{12}\) Closest to: \(\frac{1}{2}\)
Estimate the difference \(\frac{7}{8}\) – \(\frac{5}{12}\)
c. 1 – 0.5 = 0.5

Question 6.
\(\frac{9}{10}\) + \(\frac{5}{6}\)
Answer:
\(\frac{9}{10}\) + \(\frac{5}{6}\) =  1.7

Question 7.
\(\frac{11}{18}\) – \(\frac{2}{9}\)
Answer:
\(\frac{11}{18}\) – \(\frac{2}{9}\) = 0.2

Question 8.
\(\frac{1}{16}\) + \(\frac{2}{15}\)
Answer:
\(\frac{1}{16}\) + \(\frac{2}{15}\) = 0.16

Question 9.
\(\frac{24}{25}\) – \(\frac{1}{9}\)
Answer:
\(\frac{24}{25}\) – \(\frac{1}{9}\) = 0.86

Question 10.
\(\frac{3}{36}\) + \(\frac{1}{10}\)
Answer:
\(\frac{3}{36}\) + \(\frac{1}{10}\) = 0.18

Question 11.
\(\frac{37}{40}\) – \(\frac{26}{50}\)
Answer:
\(\frac{37}{40}\) – \(\frac{26}{50}\) = 0.4

Problem Solving

Question 12.
Number Sense Name two fractions that are closer to 1 than to \(\frac{1}{2}\). Then, name two fractions that are closer to \(\frac{1}{2}\) than to 0 or 1 and two other fractions that are closer to 0 than to \(\frac{1}{2}\). Find two of your fractions that have a sum of about 1\(\frac{1}{2}\).
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.8
Answer:
a(1). \(\frac{25}{30}\) = 0.8 which is closet to 1.
(2). \(\frac{9}{10}\) =  0.9 which is closet to 1.
b(1). \(\frac{5}{12}\) = 0.4 which is closet to \(\frac{1}{2}\).
(2). \(\frac{3}{6}\) = 0.5 which is closet to \(\frac{1}{2}\).
c(1).\(\frac{1}{16}\) = 0.06 which is closet to 0
(2).\(\frac{2}{30}\) = 0.06 which is closet to 0
The two fractions that have a sum of about 1\(\frac{1}{2}\) = \(\frac{25}{30}\) + \(\frac{3}{6}\) = 1.4

Question 13.
Higher Order Thinking How would you estimate whether \(\frac{27}{50}\) is closer to c or 1 without using a number line? Explain.
Answer: \(\frac{27}{50}\) is closer to \(\frac{1}{2}\).
Because I find it by dividing them \(\frac{27}{50}\) = 0.5 and \(\frac{1}{2}\) = 0.5

Use Equivalent Fractions to Add and Subtract Fractions 5

Question 14.
Katie made a bag of trail mix with \(\frac{1}{2}\) cup of raisins, \(\frac{3}{5}\) cup of banana chips, and \(\frac{3}{8}\) cup of peanuts. About how much trail mix did Katie make?
Answer: \(\frac{1}{2}\) + \(\frac{3}{5}\) + \(\frac{3}{8}\) = 1\(\frac{1}{2}\)

Question 15.
Reasoning The Annual Mug Race is the longest river sailboat race in the world. The event is run along the St. Johns River, which is 310 miles long. About how many times as long as the race is the river?
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.9
Answer: The Annual Mug Race is 42 miles and the St. Johns River, which is 310 miles long. So to find out the answer for this we need to divide the River by race so then we can find the times as answer.
310/42 = 7.4 times the river is long as the race

Assessment Practice

Question 16.
Part A
Steve is making breakfast. The recipes call for a cup of milk for grits and cup for biscuits. He only has 2 cups of milk. Does he have enough to make his breakfast? Explain.
Answer: Yes! He has enough cups of milk to make breakfast that means he has 2 cups of milk and one cup is for grits and another cup is for biscuits. So, Total 2 cups of milk.
Part B
If he has enough milk, about how much milk will he have left? If he doesn’t have enough milk, about how much will he need?
Answer: He has enough cups of milk to make breakfast that means he has 2 cups of milk and one cup is for grits and another cup is for biscuits. So, Total 2 cups of milk. He has enough cups of milk he will be left nothing at the end. If he has only one cup of milk means he need other cup of milk for biscuits.

Lesson 7.2 Find Common Denominators

Solve&Share

Sue wants \(\frac{1}{2}\) of a rectangular pan of cornbread. Dena wants of the same pan of cornbread. How should you cut the cornbread so that each girl gets the size portion she wants? Solve this problem any way you choose.

You can draw a picture to represent the pan as 1 whole. Then solve. Show your work!
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.99
Answer:-
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-30.99

Look Back! Construct Arguments Is there more than one way to divide the pan of cornbread into equal-sized parts? Explain how you know.
Answer: Sue wants half of the cornbread and Dena wants same amount. Here, we have 1 whole pan from this we gonna share into two for that we divided the whole pan into two. i.e., \(\frac{1}{2}\) = 0.5 and we have shared it to Sue and Dena.

Visual Learning Bridge

Essential Question
How Can You Find Common Denominators?

A.
Tyrone partitioned a rectangle into thirds. Sally partitioned a rectangle of the same size into fourths. How could you partition a rectangle of the same size so that you see both thirds and fourths?
You can partition a rectangle to show thirds or fourths.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.10

Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.11

B.
This rectangle is partitioned into thirds and fourths.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.12
The rectangle is partitioned into 12 equal parts. Each part is \(\frac{1}{12}\)

C.
The fractions \(\frac{1}{3}\) and \(\frac{1}{4}\) can be renamed with equivalent fractions.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.14
Fractions that have the same denominators, such as \(\frac{4}{12}\) and \(\frac{3}{12}\), are said to have common denominators.

Convince Me! Use Appropriate Tools Draw rectangles such as the ones above to find fractions equivalent to \(\frac{2}{5}\) and \(\frac{1}{3}\) that have the same denominator.
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-30.11

Another Example
Find a common denominator for \(\frac{2}{3}\) and \(\frac{5}{6}\). Then rename each fraction with an equivalent fraction.

Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 31

One Way
Multiply the denominators to find a common denominator: 3 × 6 = 18.
Write equivalent fractions with denominators of 18.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.16

Another Way
Use the fact that one denominator is a multiple of the other.
You know that 6 is a multiple of 3.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 30.17
So, \(\frac{4}{6}\) and \(\frac{5}{6}\) is one way to rename \(\frac{2}{3}\) and \(\frac{5}{6}\) with a common denominator.

Guided Practice

Do You Understand?

Question 1.
In the example on the previous page, how many twelfths are in \(\frac{1}{3}\) each section of Tyrone’s rectangle? How many twelfths are in each \(\frac{1}{4}\) section of Sally’s rectangle?
Answer:
In Tyrone’s rectangle there are \(\frac{4}{12}\) twelfths in \(\frac{1}{3}\) and there are \(\frac{3}{12}\)  are there in \(\frac{1}{4}\)

Do You Know How?

In 2 and 3, find a common denominator for each pair of fractions.

Question 2.
\(\frac{3}{8}\) and \(\frac{2}{3}\)
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-30.12

Question 3.
\(\frac{1}{6}\) and \(\frac{4}{3}\)
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-30.12

Independent Practice

In 4-11, find a common denominator for each pair of fractions. Then write equivalent fractions with the common denominator.

Question 4.
\(\frac{2}{5}\) and \(\frac{1}{6}\)
Answer:
\(\frac{2}{5}\) = \(\frac{2}{5}\) x \(\frac{6}{6}\) = \(\frac{12}{30}\)
\(\frac{1}{6}\) = \(\frac{1}{6}\) x \(\frac{5}{5}\) = \(\frac{5}{30}\)

Question 5.
\(\frac{1}{3}\) and \(\frac{4}{5}\)
Answer:
\(\frac{1}{3}\) = \(\frac{1}{3}\) x \(\frac{5}{5}\) = \(\frac{5}{5}\)
\(\frac{4}{5}\) = \(\frac{4}{5}\) x \(\frac{3}{3}\) = \(\frac{12}{15}\)

Question 6.
\(\frac{5}{8}\) and \(\frac{3}{4}\)
Answer:
\(\frac{5}{8}\)v = \(\frac{5}{8}\) x \(\frac{4}{4}\) = \(\frac{20}{32}\)
\(\frac{3}{4}\) = \(\frac{3}{4}\) x \(\frac{8}{8}\) = \(\frac{24}{32}\)

Question 7.
\(\frac{3}{10}\) and \(\frac{9}{8}\)
Answer:
\(\frac{3}{10}\) = \(\frac{3}{10}\) x \(\frac{8}{8}\) = \(\frac{24}{80}\)
\(\frac{9}{8}\) = \(\frac{9}{8}\) x \(\frac{10}{10}\) = \(\frac{90}{80}\)

Question 8.
\(\frac{3}{7}\) and \(\frac{1}{2}\)
Answer:
\(\frac{3}{7}\) = \(\frac{3}{7}\) x \(\frac{2}{2}\) = \(\frac{6}{14}\)
\(\frac{1}{2}\) = \(\frac{1}{2}\) x \(\frac{7}{7}\) = \(\frac{7}{14}\)

Question 9.
\(\frac{5}{12}\) and \(\frac{3}{5}\)
Answer:
\(\frac{5}{12}\) = \(\frac{5}{12}\) x \(\frac{5}{5}\) = \(\frac{25}{60}\)
\(\frac{3}{5}\) = \(\frac{3}{5}\) x \(\frac{12}{12}\) = \(\frac{36}{60}\)

Question 10.
\(\frac{7}{9}\) and \(\frac{2}{3}\)
Answer:
\(\frac{7}{9}\) = \(\frac{7}{9}\)  x \(\frac{3}{3}\)  = \(\frac{21}{27}\)
\(\frac{2}{3}\) = \(\frac{2}{3}\) x \(\frac{9}{9}\) = \(\frac{18}{27}\)

Question 11.
\(\frac{3}{8}\) and \(\frac{9}{20}\)
Answer:
\(\frac{3}{8}\) = \(\frac{3}{8}\) x \(\frac{20}{20}\) = \(\frac{60}{160}\)
\(\frac{9}{20}\) = \(\frac{9}{20}\) x \(\frac{8}{8}\) = \(\frac{72}{160}\)

Problem Solving

Question 12.
Critique Reasoning Explain any mistakes in the renaming of the fractions below. Show the correct renaming.
\(\frac{3}{4}\) = \(\frac{9}{12}\) \(\frac{2}{3}\) = \(\frac{6}{12}\)
Answer:
\(\frac{3}{4}\) = \(\frac{9}{12}\)
\(\frac{2}{3}\) = \(\frac{8}{12}\)

Question 13.
Higher Order Thinking For keeping business records, every three months of a year is called a quarter. How many months are equal to three-quarters of a year? Explain how you found your answer.
Answer: One quarter = \(\frac{3}{12}\) So, 3 quarters = \(\frac{9}{12}\)
Here, 12 = 12 months and 3 months = 1 quarter. Therefore, 3 + 3 + 3 = 9 months

Question 14.
Nelda baked two kinds of pasta in pans. Each pan was the same size. She sliced one pan of pasta into 6 equal pieces. She sliced the other pan into 8 equal pieces. How can the pans of pasta now be sliced so that both pans have the same-sized pieces? Draw on the pictures to show your work. If Nelda has served 6 pieces from one pan so far, what fraction of one pan has she served?
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 14.1
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-14.1
To reach her goal that both pans should have same sized pieces. So,
\(\frac{1}{6}\) x 4 pieces = \(\frac{1}{24}\). Therefore to set goal for the other pan also she needs to multiply with 3 pieces \(\frac{1}{8}\) x 3 = \(\frac{1}{24}\). So, Finally she sets her goal.
If Nelda has served 6 pieces from one pan so far, then there will be \(\frac{1}{24}\) – \(\frac{1}{6}\) = \(\frac{1}{18}\) will be left.

Question 15.
Number Sense What is the price of premium gasoline rounded to the nearest dollar? rounded to the nearest dime? rounded to the nearest penny?
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 14.2
Answer:

$4.409 to the nearest dime: $4.40

to the nearest penny: $4.41

to the nearest dollar: $4.00

Assessment Practice

Question 16.
Choose all the numbers that could be common denominators for and
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 8
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 12
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 16
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 36
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 48
Answer:

Question 17.
Choose all the numbers that could be common denominators for \(\frac{11}{12}\) and \(\frac{4}{5}\)
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 12
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 17
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 30
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 60
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 15 125
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-15

Lesson 7.3 Add Fractions with Unlike Denominators

Activity

Solve & Share

Over the weekend, Eleni ate \(\frac{1}{4}\) box of cereal, and Freddie ate \(\frac{3}{8}\) of the same box. What portion of the box of cereal did they eat in all? Solve this problem any way you choose.

Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.20

You can use fraction strips to represent adding fractions. Show your work!
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.21
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-16.21

Look Back! Make Sense and Persevere What steps did you take to solve this problem?
Answer: Step 1: Finding their common fractions for common denominator
Step2: Multiply with the factor to get common denominator.
Step3: Adding the fractions after getting the common denominator.

Visual Learning Bridge

Essential Question
How Can You Add Fractions with Unlike Denominators?

A.
Alex rode his scooter from his house to the park. Later, he rode from the park to baseball practice. How far did Alex ride?

You can add to find the total distance that Alex rode his scooter.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.23

B.
Step 1
Change the fractions to equivalent fractions with a common, or like, denominator
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.24
The number 6 is a common multiple of 2 and 3, so \(\frac{1}{2}\) and \(\frac{1}{3}\) can both be rewritten with a common denominator of 6.

Step 2
Write equivalent fractions with a common denominator.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.25

Step 3
Add the fractions to find the total number of sixths.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.26

Convince Me! Construct Arguments in the example above, would you get the same sum if you used 12 as the common denominator? Explain.
Answer:
Step 1:
Place 112 fractions strips under the 1 whole strip on your Matboard. Then place a 14 fraction strip beside the 112 strips.
Step 2:
Find fraction strips, all with the same denominator, that are equivalent to 112 and 14. Place the fraction strips under the sum. At the right, draw a picture of the model and write the equivalent fractions.
1433 = 312
112
Step 3:
Add the fractions with like denominators. Use the 1 whole strip to rename the sum in the simplest form.
312 + 112 = 412

Another Example
Find \(\frac{5}{12}\) + \(\frac{1}{4}\).
\(\frac{5}{12}\) + \(\frac{1}{4}\) = \(\frac{5}{12}\) + \(\frac{3}{12}\) Write equivalent fractions with common denominators.
= \(\frac{5+3}{12}\) = \(\frac{8}{12}\) or \(\frac{2}{3}\) Find the total number of twelfths by adding the numerators.

Guided Practice

Do You Understand?

Question 1.
In the example at the top of page 278, if the park was \(\frac{1}{8}\) mile from baseball practice instead of \(\frac{1}{3}\) mile, how far would Alex ride his scooter in all?
Answer:
\(\frac{1}{8}\) mile from baseball and \(\frac{1}{2}\) park to home then:
\(\frac{1}{8}\) = \(\frac{1}{8}\) x \(\frac{2}{2}\) = \(\frac{2}{16}\)
\(\frac{1}{2}\) = \(\frac{1}{2}\) x \(\frac{8}{8}\) = \(\frac{8}{16}\)
So, \(\frac{2}{16}\) + \(\frac{8}{16}\) = \(\frac{10}{16}\) or \(\frac{5}{8}\)

Question 2.
Vocabulary Rico and Nita solved the same problem. Rico got \(\frac{6}{8}\) for an answer, and Nita got \(\frac{3}{4}\). Which answer is correct? Use the term equivalent fraction in your explanation.
Answer:
No, They both were wrong. Rico and Nita got wrong answer. The answer is \(\frac{5}{8}\).
\(\frac{1}{8}\) mile from baseball and \(\frac{1}{2}\) park to home then:
\(\frac{1}{8}\) = \(\frac{1}{8}\) x \(\frac{2}{2}\) = \(\frac{2}{16}\)
\(\frac{1}{2}\) = \(\frac{1}{2}\) x \(\frac{8}{8}\) = \(\frac{8}{16}\)
So, \(\frac{2}{16}\) + \(\frac{8}{16}\) = \(\frac{10}{16}\) or \(\frac{5}{8}\)

 

Do You Know How?

Find the sum. Use fraction strips to help.

Question 3.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.80
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-16.80

Independent Practice

In 4 and 5, find each sum. Use fraction strips to help.

Remember that you can use multiples to find a common denominator.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.82

Question 4.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.83
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-16.83

Question 5.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 16.84
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-16.84

Problem Solving

Question 6.
Explain why the denominator 6 in \(\frac{3}{6}\) is not changed when adding the fractions.
Envision Math Common Core Grade 5 Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 17.40
Answer:
A denominator indicates how many equal pieces make one unit. If you add the denominators when adding fractions, the new denominator will not show how many equal pieces are in one unit.

Question 7.
Model with Math About \(\frac{1}{10}\) of the bones in your body are in your skull. Your hands have about \(\frac{1}{4}\) of the bones in your body. Write and solve an equation to find the fraction of the bones in your body that are in your hands or skull.
Answer:
\(\frac{1}{10}\) = \(\frac{1}{10}\) x \(\frac{4}{4}\) = \(\frac{4}{40}\)
\(\frac{1}{4}\) = \(\frac{1}{4}\) x \(\frac{10}{10}\) = \(\frac{10}{40}\)
the fraction of the bones in your body that are in your hands or skull are: \(\frac{4}{40}\) + \(\frac{10}{40}\) = \(\frac{14}{40}\)

Question 8.
enVision® STEM Of 36 chemical elements, 2 are named for women scientists and 25 are named for places. What fraction of these 36 elements are named for women or places? Show your work.
Answer:
Envision-Math-Common-Core-Grade-5-Answer-Key-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-16.80

Question 9.
Higher Order Thinking Roger made a table showing how he spends his time in one day. How many days will go by before Roger has slept the equivalent of one day? Explain how you found your answer.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.1
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-40.1

Assessment Practice

Question 10.
Which equations are true when is \(\frac{1}{2}\) is placed in the box?
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.2
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-40.2

Question 11.
Which equations are true when \(\frac{4}{7}\) placed in the box?
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.3
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-40.3

Lesson 7.4 Subtract Fractions with Unlike Denominators

Activity

Solve & Share

Rose bought the length of copper pipe shown below. She used 5 yard to repair a water line in her house. How much pipe does she have left? Solve this problem any way you choose.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.4

You can use mental math to find equivalent fractions so that \(\frac{1}{2}\) and \(\frac{4}{6}\) will have like denominators. Show your work!
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.5
Answer:-
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-40.5

Look Back! Generalize How is subtracting fractions with unlike denominators similar to adding fractions with unlike denominators?
Answer:- Subtracting fractions with unlike denominators similar to adding fractions with unlike denominators because in addition firstly we do to set denominators alike and then we add them. Same here also of unlike denominators are there we do them alike and then we subtract. Adding and subtracting is the only difference remaining all the steps are same.

Visual Learning Bridge

Essential Question How Can You Subtract Fractions with Unlike Denominators?

A.
Linda used \(\frac{1}{4}\) yard of the fabric she bought for a sewing project. How much fabric did she have left?

Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.66

You can use subtraction to find how much fabric was left.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.6

B.
Step 1
Find a common multiple of the denominators.
Multiples of 3: 3,6,9,12,…
Multiples of 4: 4, 8, 12,…
The number 12 is a multiple of 3 and 4. Write equivalent fractions with a denominator of 12 for \(\frac{2}{3}\) and \(\frac{1}{4}\).

C.
Step 2
Use the Identity Property to rename the fractions with a common denominator.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.7

C.
Step 3
Subtract the numerators.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 40.8
Linda has \(\frac{5}{12}\) yard of fabric left.

Convince Me! Critique Reasoning Suppose Linda had \(\frac{2}{3}\) of a yard of fabric and told Sandra that she used of a yard. Šandra says this is not possible. Do you agree? Explain your answer.
Answer:-  No, That is not possible because Linda had \(\frac{2}{3}\) of a yard that is 0.6 yard then how can she use 1 yard of fabric that is why Sandra says this is not possible. So, here Sandra is correct in her way and Linda cannot use the 1 yard of fabric.

Guided Practice

Do You Understand?

Question 1.
In the example on page 282, is it possible to use a common denominator greater than 12 and get the correct answer? Why or why not?
Answer: We use the common denominator by figuring common multiply factors in the fraction if in the above example if we got common factor which is greater than 12 then it is always possible to get denominator which is greater than 12.
In the above example if we got common factor as 20 then it is easy to get denominator which is actually greater than 12 and if not we have to go with the common factor either 12 or below 12.

Question 2.
In the example on page 282, if Linda had started with one yard of fabric and used \(\frac{5}{8}\) of a yard, how much fabric would be left?
Answer: Linda had one yard of fabric and she used \(\frac{5}{8}\) of a yard, The she left with 1 – \(\frac{5}{8}\) = 0.4

Do You Know How?

For 3-6, find each difference.

Question 3.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.1
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.1

Question 4.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.2
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.2

Question 5.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.3
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.3

Question 6.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.4
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.4

Independent Practice

Leveled Practice In 7-16, find each difference.

Question 7.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.5
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.5

Question 8.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.6
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.6

Question 9.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.7
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.7

Question 10.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.8
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.8

Question 11.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.9
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.9

Question 12.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.10
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-51.10

Question 13.
\(\frac{7}{10}\) – \(\frac{2}{5}\)
Answer:
\(\frac{7}{10}\) = \(\frac{7}{10}\) x \(\frac{5}{5}\) = \(\frac{21}{50}\)
\(\frac{2}{5}\) = \(\frac{2}{5}\) x \(\frac{10}{10}\) = \(\frac{20}{50}\)
\(\frac{21}{50}\) – \(\frac{20}{50}\) = \(\frac{1}{50}\)

Question 14.
\(\frac{13}{16}\) – \(\frac{1}{4}\)
Answer:
\(\frac{13}{16}\) = \(\frac{13}{16}\) x \(\frac{4}{4}\) = \(\frac{52}{64}\)
\(\frac{1}{4}\) = \(\frac{1}{4}\) x \(\frac{16}{16}\) = \(\frac{16}{64}\)
\(\frac{52}{64}\) – \(\frac{16}{64}\) = \(\frac{36}{64}\)

Question 15.
\(\frac{2}{9}\) – \(\frac{1}{6}\)
Answer:
\(\frac{2}{9}\) = \(\frac{2}{9}\) x \(\frac{6}{6}\) = \(\frac{12}{54}\)
\(\frac{1}{6}\) = \(\frac{1}{6}\) x \(\frac{9}{9}\) = \(\frac{9}{54}\)
\(\frac{12}{54}\) – \(\frac{9}{54}\) = \(\frac{3}{54}\)

Question 1
\(\frac{6}{5}\) – \(\frac{3}{8}\)
Answer:
\(\frac{6}{5}\) = \(\frac{6}{5}\) x \(\frac{8}{8}\) = \(\frac{48}{40}\)
\(\frac{3}{8}\) = \(\frac{3}{8}\) x \(\frac{5}{5}\) = \(\frac{15}{40}\)
\(\frac{48}{40}\)  – \(\frac{15}{40}\) = \(\frac{33}{40}\)

Problem Solving

Question 17.
Model with Math Write and solve an equation to find the difference between the location of Point A and Point B on the ruler.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 53.1
Answer:
Point A: \(\frac{1}{4}\)
Point B: \(\frac{2}{5}\)
Point A: \(\frac{1}{4}\) x \(\frac{5}{5}\) = \(\frac{5}{20}\)
Point B: \(\frac{2}{5}\) x \(\frac{4}{4}\) = \(\frac{8}{20}\)
Point A – Point B = \(\frac{5}{20}\) – \(\frac{8}{20}\) = \(\frac{3}{20}\)

Question 18.
Algebra Write an addition and a subtraction equation for the diagram. Then, find the missing value.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 53.2
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-53.2

Question 19.
Why do fractions need to have a common denominator before you add or subtract them?
Answer:
In order to add fractions, the fractions must have a common denominator. We need the pieces of each fraction to be the same size to combine them together. Since the pieces are all the same size, we can add these two fractions together.

Question 20.
Number Sense Without using paper and pencil, how would you find the sum of 9.8 and 2.6?
Answer: The sum of 9.8 and 2.6 is 9.8 + 2.6 = 12.4

Question 21.
Higher Order Thinking Find two fractions with a difference of \(\frac{1}{5}\) but with neither denominator equal to 5.
Answer:
There an infinite family of solutions. Any two fractions of the form:
(a+ b)/5a and b/5a
will work. Thus,
(a+b)/5a – b/5a = (a+b-b)/5a = a/5a = 1/5
of course, you can multiply each of the above fraction by 1, written as c/c, so you have c(a+b)/5ac if you wish to further obfuscate things. Similarly, you can also multiply the second fraction by 1 to get bd/5bd.
I’m sure there are other general answers as well, if an infinity of solutions is insufficient. You may wish to be sure that the product ac is even, so 5 won’t appear at all in the fraction as the last digit.

Assessment Practice

Question 22.
Choose the correct numbers from the box below to complete the subtraction sentence that follows.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.1
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-54.1

Question 23.
Choose the correct numbers from the box below to complete the subtraction sentence that follows.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.2
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-54.2

Lesson 7.5 Add and Subtract Fractions

Activity

Solver & Share
Tyler and Dean ordered pizza. Tyler ate \(\frac{1}{2}\) of the pizza and Dean ate \(\frac{1}{3}\) of the pizza. How much of the pizza was eaten, and how much is left? Solve this problem any way you choose.

Reasoning You can use number sense to help you solve this problem. Show your work!
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.3
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-54.3

Look Back! How can you check that your answer makes sense?
Answer: It is easy to identify the answer because if we want how much pizza did they eat we can directly add the amount which they have ate and if we want to know how much pizza left we easily get by subtracting both.

Visual Learning Bridge

Essential Question
How Can Adding and Subtracting Fractions Help You Solve Problems?

A.
Kayla had \(\frac{9}{10}\) gallon of paint. She painted the ceilings in her bedroom and bathroom. How much paint does she have left after painting the two ceilings?

You can use both addition and subtraction to find how much paint she has left.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.4

B.
Step 1
Add to find out how much paint Kayla used for the two ceilings.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.5
Kayla used \(\frac{13}{15}\) gallon of paint

C.
Step 2
Subtract the amount of paint Kayla used from the amount she started with.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.6
Kayla used \(\frac{1}{30}\) gallon of paint left.

Convince Me! Make Sense and Persevere For the problem above, how would you use estimation to check that the answer is reasonable?

Add to find out how much paint Kayla used for the two ceilings.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.5
Kayla used \(\frac{13}{15}\) gallon of paint.
Subtract the amount of paint Kayla used from the amount she started with.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.6
Kayla used \(\frac{1}{30}\) gallon of paint left.

Guided Practice

Do You Understand?

Question 1.
In the example on page 286, how much more paint did Kayla use to paint the bedroom ceiling than the bathroom ceiling?
Answer:
Add to find out how much paint Kayla used for the two ceilings.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 54.5

Question 2.
Number Sense Kevin estimated the difference of \(\frac{9}{10}\) – \(\frac{4}{8}\) to be 0. Is his estimate reasonable? Explain.
Answer:
\(\frac{9}{10}\) = \(\frac{9}{10}\) x \(\frac{8}{8}\) = \(\frac{72}{80}\)
\(\frac{4}{8}\) = \(\frac{4}{8}\)  x \(\frac{10}{10}\)  = \(\frac{40}{80}\)
\(\frac{72}{80}\) – \(\frac{40}{80}\) = \(\frac{32}{80}\) = 0.4
Kevin estimated the difference of \(\frac{9}{10}\) – \(\frac{4}{8}\) to be 0 and his estimation was wrong because 0.4 is closest to \(\frac{1}{2}\) not closest to 0

Do You Know How?

For 3-6, find the sum or difference.

Question 3.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.1
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-55.1

Question 4.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.2
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-55.2

Question 5.
\(\frac{7}{8}\) – \(\frac{3}{6}\)
Answer:
\(\frac{7}{8}\) = \(\frac{7}{8}\) x \(\frac{6}{6}\) = \(\frac{42}{48}\)
\(\frac{3}{6}\) = \(\frac{3}{6}\) x \(\frac{8}{8}\) = \(\frac{24}{48}\)
\(\frac{42}{48}\) – \(\frac{24}{48}\) = \(\frac{18}{48}\)

Question 6.
\(\frac{7}{8}\) + (\(\frac{4}{8}\) – \(\frac{2}{4}\))
Answer:
\(\frac{4}{8}\) = \(\frac{4}{8}\) x \(\frac{4}{4}\) = \(\frac{16}{32}\)
\(\frac{2}{4}\) = \(\frac{2}{4}\) x \(\frac{8}{8}\) = \(\frac{16}{32}\)
\(\frac{16}{32}\) – \(\frac{16}{32}\) = \(\frac{16}{32}\) = 0
\(\frac{7}{8}\) + (0) = \(\frac{7}{8}\)

Independent Practice

In 7-22, find the sum or difference.

Question 7.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.3
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-55.3

Question 8.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.4
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-55.4

Question 9.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 550
Answer:
Envision-Math-Common-Core-Grade-5-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-550

Question 10.
Envision Math Common Core 5th Grade Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.5
Answer:
Envision-Math-Common-Core-5th-Grade-Answers-Topic-7-Use-Equivalent-Fractions-to-Add-and-Subtract-Fractions-55.5

Question 11.
\(\frac{17}{15}\) – \(\frac{1}{3}\)
Answer:
\(\frac{17}{15}\) = \(\frac{17}{15}\)  x \(\frac{3}{3}\) = \(\frac{51}{45}\)
\(\frac{1}{3}\) = \(\frac{1}{3}\) x \(\frac{15}{15}\) = \(\frac{15}{45}\)
\(\frac{51}{45}\) –  \(\frac{15}{45}\) = \(\frac{36}{45}\)

Question 12.
\(\frac{7}{16}\) + \(\frac{3}{8}\)
Answer:
\(\frac{7}{16}\) = \(\frac{7}{16}\)  x \(\frac{8}{8}\)  = \(\frac{56}{128}\)
\(\frac{3}{8}\) = \(\frac{3}{8}\) x \(\frac{16}{16}\) = \(\frac{48}{128}\)
\(\frac{56}{128}\)  + \(\frac{48}{128}\)  = \(\frac{8}{128}\)

Question 13.
\(\frac{2}{5}\) + \(\frac{1}{4}\)
Answer:
\(\frac{8}{20}\) + \(\frac{5}{20}\) = \(\frac{13}{20}\)

Question 14.
\(\frac{1}{7}\) + \(\frac{1}{2}\)
Answer:
\(\frac{2}{14}\) + \(\frac{7}{14}\) = \(\frac{9}{14}\)

Question 15.
\(\frac{1}{2}\) – \(\frac{3}{16}\)
Answer:
\(\frac{16}{32}\) – \(\frac{6}{32}\) = \(\frac{10}{32}\)

Question 16.
\(\frac{7}{8}\) – \(\frac{2}{3}\)
Answer:
\(\frac{14}{24}\) – \(\frac{16}{24}\) = – \(\frac{2}{24}\)

Question 17.
\(\frac{11}{12}\) – \(\frac{4}{6}\)
Answer:
\(\frac{66}{72}\) – \(\frac{48}{72}\) = \(\frac{18}{72}\)

Question 18.
\(\frac{7}{18}\) + \(\frac{5}{9}\)
Answer:
\(\frac{63}{162}\) + \(\frac{90}{162}\) = \(\frac{153}{162}\)

Question 19.
(\(\frac{7}{8}\) + \(\frac{1}{12}\)) – \(\frac{1}{2}\)
Answer:
\(\frac{84}{108}\) + \(\frac{8}{108}\) = \(\frac{92}{108}\)

\(\frac{184}{216}\) – \(\frac{92}{216}\) = \(\frac{92}{216}\)

Question 20.
(\(\frac{11}{18}\) – \(\frac{4}{9}\)) + \(\frac{1}{6}\)
Answer:
\(\frac{99}{162}\) – \(\frac{72}{162}\) = \(\frac{29}{162}\)
\(\frac{174}{648}\) + \(\frac{162}{648}\) = \(\frac{12}{648}\)

Question 21.
\(\frac{13}{14}\) – (\(\frac{1}{2}\) + \(\frac{2}{7}\))
Answer:
\(\frac{7}{14}\) + \(\frac{4}{14}\) = \(\frac{11}{14}\)
\(\frac{13}{14}\) – \(\frac{11}{14}\) = \(\frac{2}{14}\)

Question 22.
\(\frac{1}{6}\) + (\(\frac{15}{15}\) – \(\frac{7}{10}\))
Answer:
\(\frac{150}{150}\) – \(\frac{105}{150}\) = \(\frac{45}{150}\)
\(\frac{150}{900}\) + \(\frac{270}{900}\) = \(\frac{420}{900}\)

Problem Solving

Question 23.
The table shows the amounts of ingredients needed to make a pizza. How much more cheese do you need than pepperoni and mushrooms combined? Show how you solved the problem.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 56.2
Answer:

Question 24.
Charlie’s goal is to use less than 50 gallons of water per day. His water bill for the month showed that he used 1,524 gallons of water in 30 days. Did Charlie meet his goal this month? Explain how you decided.
Answer:

Question 25.
Construct Arguments Jereen spent \(\frac{1}{4}\) hour on homework before school, another \(\frac{1}{2}\) hour after she got home, and a final \(\frac{1}{3}\) hour after dinner. Did she spend more or less than 1 hour on homework in all? Explain.
Answer:

Question 26.
Carl has three lengths of cable, \(\frac{5}{6}\) yard long, \(\frac{1}{4}\) yard long, and \(\frac{2}{3}\) yard long. If he uses 1 yard of cable, how much cable is left? Explain your work.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 56.40
Answer:

Question 27.
Higher Order Thinking Find two fractions with a sum of \(\frac{2}{3}\) but with neither denominator equal to 3.
Answer:

Assessment Practice

Question 28.
What fraction is missing from the following equation?

A. \(\frac{4}{12}\)
B. \(\frac{3}{8}\)
C. \(\frac{5}{12}\)
D. \(\frac{8}{8}\)
Answer:

Question 29.
What is the value of the expression?
\(\frac{1}{4}\) + \(\frac{1}{4}\) + \(\frac{3}{8}\)
A. \(\frac{5}{8}\)
B. \(\frac{7}{8}\)
C. \(\frac{7}{16}\)
D. \(\frac{7}{32}\)
Answer:

Lesson 7.6 Estimate Sums and Differences of Mixed Numbers

Activity

Solve&Share

Alex has five cups of strawberries. He wants to use 1\(\frac{3}{4}\) cups of strawberries for a fruit salad and 3\(\frac{1}{2}\) cups for jam. Does Alex have enough strawberries to make both recipes? Solve this problem any way you choose.

Generalize You can estimate because you just need to know if Alex has enough. Show your work!
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 57.1

Look Back! Does it make sense to use 1 cup and 3 cups to estimate if Alex has enough strawberries? Explain.

Visual Learning Bridge

Essential Question What Are Some Ways to Estimate?

A.
Jamila’s mom wants to make a size 10 dress and jacket. About how many yards of fabric does she need?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 57.2

B.
One Way
Use a number line to round fractions and mixed numbers to the nearest whole number
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 57.3
Jamila’s mom needs about 4 yards of fabric.

C.
Another Way
Use \(\frac{1}{2}\) as a benchmark fraction.
Replace each fraction with the nearest \(\frac{1}{2}\) unit.
1\(\frac{5}{8}\) is close to 1\(\frac{1}{2}\).
2\(\frac{1}{4}\) is halfway between 2 and 2\(\frac{1}{2}\)

You can replace 2\(\frac{1}{4}\) with 2\(\frac{1}{2}\).
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 57.4
So, 2\(\frac{1}{4}\) + 1\(\frac{5}{8}\) is about 2\(\frac{1}{2}\) + 1\(\frac{1}{2}\) = 4.

Convince Me! Critique Reasoning In Box C above, why does it make sense to replace 2\(\frac{1}{4}\) with 2\(\frac{1}{2}\) rather than 2?

Guided Practice

Do You Understand?

Question 1.
To estimate with mixed numbers, when should you round to the next greater whole number?
Answer:

Question 2.
When should you estimate a sum or difference?
Answer:

Do You Know How?

In 3-5, round to the nearest whole number.

Question 3.
2\(\frac{3}{4}\)
Answer:

Question 4.
1\(\frac{5}{7}\)
Answer:

Question 5.
2\(\frac{3}{10}\)
Answer:

In 6 and 7, estimate each sum or difference using benchmark fractions.

Question 6.
2\(\frac{5}{9}\) – 1\(\frac{1}{3}\)
Answer:

Question 7.
2\(\frac{4}{10}\) + 3\(\frac{5}{8}\)
Answer:

Independent Practice

Leveled Practice In 8-11, use the number line to round the mixed numbers to the nearest whole numbers.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 58.1

Question 8.
11\(\frac{4}{6}\)
Answer:

Question 9.
11\(\frac{2}{8}\)
Answer:

Question 10.
11\(\frac{8}{12}\)
Answer:

Question 11.
11\(\frac{4}{10}\)
Answer:

In 12-20, estimate each sum or difference.

Question 12.
2\(\frac{1}{8}\) – \(\frac{5}{7}\)
Answer:

Question 13.
12\(\frac{1}{3}\) + 2\(\frac{1}{4}\)
Answer:

Question 14.
2\(\frac{2}{3}\) + \(\frac{7}{8}\) + 6\(\frac{7}{12}\)
Answer:

Question 15.
1\(\frac{10}{15}\) – \(\frac{8}{9}\)
Answer:

Question 16.
10\(\frac{5}{6}\) – 2\(\frac{3}{8}\)
Answer:

Question 17.
12\(\frac{8}{25}\) + 13\(\frac{5}{9}\)
Answer:

Question 18.
48\(\frac{1}{10}\) – 2\(\frac{7}{9}\)
Answer:

Question 19.
33\(\frac{14}{15}\) + 23\(\frac{9}{25}\)
Answer:

Question 20.
14\(\frac{4}{9}\) + 25\(\frac{1}{6}\) + 7\(\frac{11}{18}\)
Answer:

Problem Solving

Question 21.
Use the recipes to answer the questions.
a. Estimate how many cups of Fruit Trail Mix the recipe can make.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 85.2
b Estimate how many cups of Traditional Trail Mix the recipe can make.
c Estimate how much trail mix you would have if you made both recipes.
Answer:

Question 22.
Kim is 3\(\frac{5}{8}\) inches taller than Colleen. If Kim is 60 inches tall, what is the best estimate of Colleen’s height?
Answer:

Question 23.
Higher Order Thinking Last week Jason walked 3\(\frac{1}{4}\) miles each day for 3 days and 4\(\frac{5}{8}\). miles each day for 4 days. About how many miles did Jason walk last week?
Answer:

Question 24.
Make Sense and Persevere Cal has $12.50 to spend. He wants to ride the roller coaster twice and the Ferris wheel once. Does Cal have enough money? Explain. What are 3 possible combinations of rides Cal can take using the money he has?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 85.6
Answer:

Assessment Practice

Question 25.
Liam used 2\(\frac{2}{9}\) cups of milk for a pancake recipe and drank another 93 cups of milk. About how much milk did he use in all?
A. 8 cups
B. 10 cups
C. 12 cups
D. 13 cups
Answer:

Question 26.
Annie has 13\(\frac{1}{2}\) yards of string. She uses 1\(\frac{9}{10}\) yards to fix her backpack. About how much string does she have left?
A. 11 yards
B. 12 yards
C. 14 yards
D. 15 yards
Answer:

Lesson 7.7 Use Models to Add Mixed Numbers

Solve&Share
Martina is baking bread. She mixes 1\(\frac{3}{4}\) cups of flour with other ingredients. Then she adds 4\(\frac{1}{2}\) cups of flour to the mixture. How many cups of flour does she need? Solve this problem any way you choose.

Use Appropriate Tools You can use fraction strips to help add mixed numbers. Show your work!
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 87.1

Look Back! Explain how you can estimate the sum above.

Visual Learning Bridge

Essential Question How Can You Model Addition master of Mixed Numbers?

A.
Bill has 2 boards he will use to make picture frames. What is the total length of the boards Bill has to make picture frames?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 87.2
You can find a common denominator to add the fractions.

B.
Step 1
Rename the fractional parts as equivalent fractions with a like denominator. Add the fractions.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 87.3

C.
Step 2
Add the whole number parts.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 87.4
Then add the sum of the fractional parts.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 87.5
The total length of the boards is 4\(\frac{1}{4}\) feet.

Convince Me! Critique Reasoning Tom has 2 boards that are the same length as Bill’s. He says that he found the total length of the boards by adding 28 twelfths and 23 twelfths. Does his method work? Explain.

Guided Practice

Do You Understand?

Question 1.
When adding two mixed numbers, does it ever make sense to rename the fractional sum? Explain.
Answer:

Do You Know How?

In 2-5, use fraction strips to find each sum.

Question 2.
1\(\frac{1}{10}\) + 2\(\frac{4}{5}\)
Answer:

Question 3.
1\(\frac{1}{2}\) + 2\(\frac{3}{4}\)
Answer:

Question 4.
3\(\frac{2}{3}\) + 1\(\frac{4}{6}\)
Answer:

Question 5.
3\(\frac{1}{6}\) + 2\(\frac{2}{3}\)
Answer:

Independent Practice

Leveled Practice In 6 and 7, use each model to find the sum.

Question 6.
Charles used 1\(\frac{2}{3}\) cups of walnuts and 2\(\frac{1}{6}\) cups of cranberries to make breakfast bread. How many cups of walnuts and cranberries did he use in all?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.1
Answer:

Question 7.
Mary worked 2\(\frac{3}{4}\) hours on Monday and 1\(\frac{1}{2}\) hours on Tuesday. How many hours did she work in all on Monday and Tuesday?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.2
Answer:

In 8-16, use fraction strips to find each sum.

Question 8.
2\(\frac{6}{10}\) + 1\(\frac{3}{5}\)
Answer:

Question 9.
4\(\frac{5}{6}\) + 1\(\frac{7}{12}\)
Answer:

Question 10.
4\(\frac{2}{5}\) + 3\(\frac{7}{10}\)
Answer:

Question 11.
3\(\frac{1}{2}\) +1\(\frac{3}{4}\)
Answer:

Question 12.
1\(\frac{7}{8}\) + 5\(\frac{1}{4}\)
Answer:

Question 13.
2\(\frac{6}{12}\) + 1\(\frac{1}{2}\)
Answer:

Question 14.
3\(\frac{2}{5}\) + 1\(\frac{9}{10}\)
Answer:

Question 15.
2\(\frac{7}{12}\) + 1\(\frac{3}{4}\)
Answer:

Question 16.
2\(\frac{7}{8}\) + 5\(\frac{1}{2}\)
Answer:

Problem Solving

Question 17.
Lindsey used 1\(\frac{1}{4}\) gallons of tan paint for the ceiling and 4\(\frac{3}{8}\). gallons of green paint for the walls of her kitchen. How much paint did Lindsey use in all? Use fraction strips to help
Answer:

Question 18.
Paul said, “I walked 2\(\frac{1}{2}\) miles on Saturday and 2\(\frac{3}{4}\) miles on Sunday.” How many miles is that in all?
Answer:

Question 19.
Higher Order Thinking Tori is making muffins. The recipe calls for 2\(\frac{5}{6}\) cups of brown sugar for the muffins and 1\(\frac{1}{3}\) cups of brown sugar for the topping. Tori has 4 cups of brown sugar. Does she have enough brown sugar to make the muffins and the topping? Explain.

You can use fraction strips or a number line to compare amounts.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.5

In 20 and 21, use the map. Each unit represents one block.

Question 20.
Ben left the museum and walked 4 blocks to his next destination. What was Ben’s destination?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.9
Answer:

Question 21.
Make Sense and Persevere Ben walked from the restaurant to the bus stop. Then, he took the bus to the stadium. If he took the shortest route, how many blocks did Ben travel? Note that Ben can only travel along the grid lines.
Answer:

Assessment Practice

Question 22.
Marta used 2\(\frac{3}{4}\) cups of milk and 15 cups of cheese in a recipe. How many cups of cheese and milk did Marta use?
A. 3 cups
B. 3\(\frac{4}{6}\) cups
C. 4\(\frac{1}{4}\) cups
D. 4\(\frac{3}{4}\) cups
Answer:

Question 23.
Garrett ran 21\(\frac{1}{2}\) miles last week. He ran 17\(\frac{7}{8}\) miles this week. How many miles did he run in all?
A. 38 miles
B. 38\(\frac{1}{2}\) miles
C. 39\(\frac{3}{8}\) miles
D. 39\(\frac{7}{8}\) miles
Answer:

Lesson 7.8 Add Mixed Numbers

Solve & Share
Joaquin used two types of flour in a muffin recipe. How much flour did he use in all? Solve any way you choose.

Use Structure Use what you know about adding fractions. Show your work!
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.10

Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.11

Look Back! How is adding mixed numbers with unlike denominators the same as adding fractions with unlike denominators? How is it different?

Visual Learning Bridge

Essential Question How Can You Add Mixed Numbers?

You can use addition to find the total amount of soil.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.13

A.
Rhoda mixes 1\(\frac{1}{2}\) cups of sand with 2\(\frac{2}{3}\) cups of potting mixture to prepare soil for her cactus plants. After mixing them together, how many cups of soil does Rhoda have?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.14

B.
Step 1
Find 2\(\frac{2}{3}\) + 1\(\frac{1}{2}\).
Write equivalent fractions with a common denominator.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.15

C.
Step 2
Add the fractions.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.16

C.
Step 3
Add the whole numbers.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.17

Convince Me! Critique Reasoning Kyle used 9 as an estimate for 3\(\frac{1}{6}\) + 5\(\frac{7}{8}\). He got 9\(\frac{1}{24}\) for the exact sum. Is his calculated answer reasonable? Explain.

Guided Practice

Do You Understand?

Question 1.
How is adding mixed numbers like adding fractions and whole numbers?
Answer:

Question 2.
Look at the example on page 298. Why is the denominator 6 used in the equivalent fractions?
Answer:

Do You Know How?

In 3-6, estimate and then find each sum.

Question 3.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.60
Answer:

Question 4.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.61
Answer:

Question 5.
4\(\frac{1}{9}\) + 1\(\frac{1}{3}\)
Answer:

Question 6.
6\(\frac{5}{12}\) + 4\(\frac{5}{8}\)
Answer:

Independent Practice

Leveled Practice In 7-18, estimate and then find each sum.

Remember, fractions must have a common, or like, denominator before they can be added.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 80.66

Question 7.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.3
Answer:

Question 8.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.4
Answer:

Question 9.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.5
Answer:

Question 10.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.6
Answer:

Question 11.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.7
Answer:

Question 12.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.8
Answer:

Question 13.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.9
Answer:

Question 14.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 42.10
Answer:

Question 15.
2\(\frac{3}{4}\) + 7\(\frac{3}{5}\)
Answer:

Question 16.
3\(\frac{8}{9}\) + 8\(\frac{1}{2}\)
Answer:

Question 17.
1\(\frac{7}{12}\) + 2\(\frac{3}{8}\)
Answer:

Question 18.
3\(\frac{11}{12}\) + 9\(\frac{1}{16}\)
Answer:

Problem Solving

Question 19.
Use the map to find the answer.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.1
a What is the distance from the start to the end of the trail?
b Louise walked from the start of the trail to the bird lookout and back. Did she walk a longer or shorter distance than if she had walked from the start of the trail to the end? Explain.
c Another day, Louise walked from the start of the trail to the end. At the end, she realized she forgot her binoculars at the bird lookout. She walked from the end of the trail to the bird lookout and back. What is the total distance she walked?
Answer:

Question 20.
Higher Order Thinking Twice a day Cameron’s cat eats 4 ounces of dry cat food and 2 ounces of wet cat food. Dry food comes in 5-pound bags. Wet food comes in 6-ounce cans.
a How many cans of wet food should he buy to feed his cat for a week?
b How many ounces of wet cat food will be left over at the end of the week?
c How many days can he feed his cat from a 5-pound bag of dry food?

Remember: There are 16 ounces in a pound.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 58.50

Question 21.
Julia bought 12 bags of cucumber seeds. Each bag contains 42 seeds. If she plants one half of the seeds, how many seeds does she have left?
Answer:

Question 22.
Critique Reasoning John added 2\(\frac{7}{12}\) and 5\(\frac{2}{3}\) and got 7\(\frac{1}{4}\) as the sum. Is John’s answer reasonable? Explain.
Answer:

Assessment Practice

Question 23.
What is the missing number in the following equation?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.7
Answer:

Question 24.
Arnie skated 1\(\frac{3}{4}\) miles from home to the lake. He skated 1\(\frac{1}{3}\) miles around the lake, and then skated back home. Write an addition sentence to show how many miles Arnie skated in all.
Answer:

Lesson 7.9 Use Models to Subtract Mixed Numbers

Solve & Share
Clara and Erin volunteered at an animal shelter a total of 9\(\frac{5}{6}\) hours. Clara worked for 4\(\frac{1}{3}\) hours. How many hours did Erin work? You can use fraction strips to solve this problem.

Generalize How can you use what you know about adding mixed numbers to help you subtract mixed numbers? Show your work!
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.8

Look Back! How can you estimate the difference for the problem above? Explain your thinking.

Visual Learning Bridge

Essential Question How Can You Model Subtraction question of Mixed Numbers?

A.
James needs 1\(\frac{11}{12}\) inches of pipe to repair a small part of a bicycle frame. He has a pipe that is 2\(\frac{1}{2}\) inches long. Does he have enough pipe left over to fix a \(\frac{3}{4}\)-inch piece of frame on another bike?

Rename 2\(\frac{1}{2}\) as 2\(\frac{6}{12}\) that the fractions have a common denominator.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.9

B.
Step 1
Model the number you are subtracting from, 2\(\frac{6}{12}\)
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.10
If the fraction you will be subtracting is greater than the fraction part of the number you model, rename 1 whole.
Since \(\frac{11}{12}\) > \(\frac{6}{12}\), rename 1 whole as \(\frac{12}{12}\).
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.11

Step 2
Use your renamed model to cross out the number that you are subtracting, 1\(\frac{11}{12}\)
There are \(\frac{7}{12}\) left.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 50.30
So, 2\(\frac{1}{2}\) – 1\(\frac{11}{12}\) = \(\frac{7}{12}\)
James will have \(\frac{7}{12}\) inch of pipe left. He does not have enough for the other bike.

Convince Me! Use Appropriate Tools Use fraction strips to find 5\(\frac{1}{2}\) – 2\(\frac{3}{4}\).

Guided Practice

Do You Understand?

Question 1.
When subtracting two mixed numbers, is it always necessary to rename one of the wholes? Explain.

Do You Know How?

In 2-5, use fraction strips to find each difference.

Question 2.
4\(\frac{5}{6}\) – 2\(\frac{1}{3}\)
Answer:

Question 3.
4\(\frac{1}{8}\) – 3\(\frac{3}{4}\)
Answer:

Question 4.
5\(\frac{1}{2}\) – 2\(\frac{5}{6}\)
Answer:

Question 5.
5\(\frac{4}{10}\) – 3\(\frac{4}{5}\)
Answer:

Independent Practice

In 6 and 7, use each model to find the difference.

Question 6.
Terrell lives 2\(\frac{5}{6}\) blocks away from his best friend. His school is 4\(\frac{1}{3}\) blocks away in the same direction. If he stops at his best friend’s house first, how much farther do they have to walk to school?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.6
Answer:

Question 7.
Tina bought 3\(\frac{1}{2}\) pounds of turkey and 2\(\frac{1}{4}\) pounds of cheese. She used 1\(\frac{1}{2}\) pounds of cheese to make macaroni and cheese. How much cheese does she have left?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 51.7
Answer:

In 8-15, use fraction strips to find each difference.

Question 8.
12\(\frac{3}{4}\) – 9\(\frac{5}{8}\)
Answer:

Question 9.
8\(\frac{1}{6}\) – 7\(\frac{2}{3}\)
Answer:

Question 10.
13\(\frac{7}{9}\) – 10\(\frac{2}{3}\)
Answer:

Question 11.
3\(\frac{1}{12}\) – 2\(\frac{3}{4}\)
Answer:

Question 12.
6\(\frac{3}{4}\) – 3\(\frac{11}{12}\)
Answer:

Question 13.
4\(\frac{3}{5}\) – 1\(\frac{1}{10}\)
Answer:

Question 14.
6\(\frac{1}{2}\) – 3\(\frac{7}{10}\)
Answer:

Question 15.
6\(\frac{2}{3}\) – 4\(\frac{2}{9}\)
Answer:

Problem Solving

For 16 and 17, use the table at the right.

Question 16.
How much longer is a Red Oak leaf than a Sugar Maple leaf? Write an equation to model your work.
Answer:

Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 53.4

Question 17.
How much longer is a Red Oak leaf than a Paper Birch leaf? Write an equation to model your work.

Question 18.
Higher Order Thinking Lemmy walked 3\(\frac{1}{2}\) miles on Saturday and 4\(\frac{3}{4}\) miles on Sunday. Ronnie walked 5\(\frac{3}{8}\) miles on Saturday. Who walked farther? How much farther?
Answer:

Question 19.
Model with Math Jamal is buying lunch for his family. He buys 4 drinks that each cost $1.75 and 4 sandwiches that each cost $7.50. If the prices include tax and he also leaves a $7 tip, how much does he spend in all? Write equations to show your work.
Answer:

Assessment Practice

Question 20.
What is the missing number in the following equation?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.2
Answer:

Question 21.
What is the missing number in the following equation?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.3
Answer:

Lesson 7.10 Subtract Mixed Numbers

Solve&Share
Evan walks 2-miles to his aunt’s house. He has already walked mile. How much farther does he have to go? Solve this problem any way you choose.

Use Structure Use what you know about subtracting fractions. Show your work!
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 55.33

Look Back! Jon said, “Changing \(\frac{3}{4}\) to \(\frac{6}{8}\) makes this problem easier.” What do you think Jon meant?

Visual Learning Bridge

Essential Question How Can You Subtract Mixed Numbers?

A.
A golf ball measures about 1\(\frac{2}{3}\) inches across the center. What is the difference between the distance across the center of the hole and the golf ball?
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.1

You can use subtraction to find the difference.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.2

B.
Step 1
Write equivalent fractions with a common denominator.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.3

C.
Step 2
Rename 4\(\frac{3}{12}\) to show more twelfths.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.4

D.
Step 3
Subtract the fractions. Then subtract the whole numbers.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.5
The hole is 2\(\frac{7}{12}\) inches wider.

Convince Me! Critique Reasoning Estimate 8\(\frac{1}{3}\) – 3\(\frac{3}{4}\). Tell how you got your estimate. Susi subtracted and found the actual difference to be 5\(\frac{7}{12}\). Is her answer reasonable? Explain.

Another Example
Sometimes you may have to rename a whole number to subtract. Find the difference of 6 – 2\(\frac{3}{8}\).
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.6

Guided Practice

Do You Understand?

Question 1.
In the example above, why do you need to rename the 6?
Answer:

Question 2.
In the example on page 306, could two golf balls fall into the hole at the same time? Explain your reasoning.
Answer:

In 3-6, estimate and then find each difference.

Question 3.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.20
Answer:

Question 4.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.21
Answer:

Question 5.
6\(\frac{3}{10}\) – 1\(\frac{4}{5}\)
Answer:

Question 6.
9\(\frac{1}{3}\) – 4\(\frac{3}{4}\)
Answer:

Independent Practice

In 7-18, estimate and then find each difference.

Remember to check that your answer makes sense by comparing it to the estimate.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.25

Question 7.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.26
Answer:

Question 8.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.27
Answer:

Question 9.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.28
Answer:

Question 10.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.29
Answer:

Question 11.
6\(\frac{1}{3}\) – 5\(\frac{2}{3}\)
Answer:

Question 12.
9\(\frac{1}{2}\) – 6\(\frac{3}{4}\)
Answer:

Question 13.
8\(\frac{3}{16}\) – 3\(\frac{5}{8}\)
Answer:

Question 14.
7\(\frac{1}{2}\) – \(\frac{7}{10}\)
Answer:

Question 15.
15\(\frac{1}{6}\) – 4\(\frac{3}{8}\)
Answer:

Question 16.
13\(\frac{1}{12}\) – 8\(\frac{1}{4}\)
Answer:

Question 17.
6\(\frac{1}{3}\) – 2\(\frac{3}{5}\)
Answer:

Question 18.
10\(\frac{5}{12}\) – 4\(\frac{7}{8}\)
Answer:

Problem Solving

Question 19.
The average weight of a basketball is 21\(\frac{1}{10}\) ounces. The average weight of a baseball is 5\(\frac{1}{4}\) ounces. How many more ounces does the basketball weigh? Write the missing numbers in the diagram.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.30
Answer:

Question 20.
enVision® STEM The smallest mammals on Earth are the bumblebee bat and the Etruscan pygmy shrew. The length of a certain bumblebee bat is 1\(\frac{9}{50}\) inches. The length of a certain Etruscan pygmy shrew is 1\(\frac{21}{50}\) inches. How much smaller is the bat than the shrew?
Answer:

Question 21.
Be Precise How are the purple quadrilateral and the green quadrilateral alike? How are they different?
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.31
Answer:

Question 22.
Higher Order Thinking Sam used the model to find 2\(\frac{5}{12}\) – 1\(\frac{7}{12}\). Did Sam model the problem correctly? Explain. If not, show how the problem should have been modeled and find the difference.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.32
Answer:

Assessment Practice

Question 23.
Choose the correct number from the box below to complete the subtraction sentence that follows.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.33
Answer:

Question 24.
Choose the correct number from the box below to complete the subtraction sentence that follows.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.34
Answer:

Lesson 7.11 Add and Subtract Mixed Numbers

Activity

Solve&Share
Tim has 15 feet of wrapping paper. He uses 4\(\frac{1}{3}\) feet for his daughter’s present and 5\(\frac{3}{8}\) feet for his niece’s present. How much wrapping paper does Tim have left? Solve this problem any way you choose.

Reasoning What steps are needed to solve the problem? Show your work!
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 86.42

Look Back! In the problem above, how could you have estimated the amount of wrapping paper that is left?

Visual Learning Bridge

Essential Question
How Can Adding and Subtracting Mixed Numbers Help You Solve Problems?

A.
Clarisse has two lengths of fabric to make covers for a sofa and chair. The covers require 9\(\frac{2}{3}\) yards of fabric. How much fabric will Clarisse have left?

Find a common denominator when adding and subtracting fractions.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 63.1

B.
Step 1
Add to find out how much fabric Clarisse has in all.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 63.2
Clarisse has 13\(\frac{7}{12}\) yards of fabric in all.

C.
Step 2
Subtract the amount she will use from the total length of fabric.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 63.3
Clarisse will have 3\(\frac{11}{12}\) yards of fabric left.

Convince Me! Make Sense and Persevere Clarisse has 14\(\frac{3}{4}\) yards of fabric to cover another sofa and chair. The new sofa needs 9\(\frac{1}{6}\) yards of fabric and the new chair needs 4\(\frac{1}{3}\) yards of fabric. Estimate to decide if Clarisse has enough fabric. If so, how much fabric will she have left?

Guided Practices

Do You Understand?

Question 1.
In the example on page 310, why do you add before you subtract?
Answer:

Question 2.
In the example on page 310, does Clarisse have enough fabric left over to make two cushions that each use 2\(\frac{7}{12}\) yards of fabric? Explain.
Answer:

Do You Know How?

In 3-5, find the sum or difference.

Question 3.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.1
Answer:

Question 4.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.2
Answer:

Question 5.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.3
Answer:

In 6-9, solve. Do the addition in the parentheses first.

Question 6.
4\(\frac{3}{5}\) + 11\(\frac{2}{15}\)
Answer:

Question 7.
8\(\frac{2}{3}\) – 3\(\frac{3}{4}\)
Answer:

Question 8.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 639
Answer:

Question 9.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 640
Answer:

Independent Practice

In 10-14, find each sum or difference.

Question 10.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.10
Answer:

Question 11.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.11
Answer:

Question 12.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.12
Answer:

Question 13.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.13
Answer:

Question 14.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 66.14
Answer:

In 15-20, solve. Do the operation in the parentheses first.

Question 15.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.3
Answer:

Question 16.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.4
Answer:

Question 17.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.5
Answer:

Question 18.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.6
Answer:

Question 19.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.7
Answer:

Question 20.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.8
Answer:

Problem Solving

In 21-23, use the table below.

Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 70.9

Question 21.
Be Precise How much longer is the maximum jump of a South African sharp-nosed frog than the maximum jump of a leopard frog?
Answer:

Question 22.
How many centimeters long is a bullfrog? Round to the nearest whole number.
Answer:

Question 23.
Higher Order Thinking Which frog jumps about 10 times its body length? Explain how you found your answer.
Answer:

Question 24.
A-Z Vocabulary Write three numbers that are common denominators of \(\frac{7}{15}\) and \(\frac{3}{5}\).
Answer:

Question 25.
Marie plants 12 packages of vegetable seeds in a community garden. Each package costs $1.97 with tax. What is the total cost of the seeds?
Answer:

Assessment Practice

Question 26.
Which equations are true when 5\(\frac{3}{8}\) is placed in the box?
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 77.1
Answer:

Question 27.
Which equations are true when 3\(\frac{1}{3}\) is placed in the box?
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 77.2
Answer:

Lesson 7.12 Model with Math

Problem Solving

Solve & Share
Annie found three seashells at the beach. How much shorter is the Scotch Bonnet seashell than the combined lengths of the two Alphabet Cone seashells? Solve this problem any way you choose. Use a diagram to help.

Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 77.9

Thinking Habits
Be a good thinker! These questions can help you.
• How can I use math I know to help solve this problem?
• How can I use pictures, objects, or an equation to represent the problem?
• Can I write an equation to show the problem?
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 77.25

Look Back! Model with Mathematics What is another way to represent this problem?

Visual Learning Bridge

Essential Question How Can You Represent a Problem Question with a Bar Diagram?

A.
The first step of a recipe is to mix the flour, white sugar, and brown sugar. Will a bowl that holds 4 cups be large enough?

Use a model to represent the problem.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 72.8

What do I need to do to solve the problem?
I need to find the total amount of the first three ingredients and compare that amount to 4 cups.

Here’s my thinking.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 72.9

B.
How can I model with math?

I can
• use math I know to help solve this problem.
• use a diagram to represent and solve this problem.
• write an equation involving fractions or mixed numbers.
• decide if my results make sense.

C.
I will use a bar diagram and an equation to represent the situation.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 72.10
I can write this answer as a mixed number. 2\(\frac{6}{4}\) = 3\(\frac{2}{4}\) or 3\(\frac{1}{2}\)
There are 3\(\frac{1}{2}\) cups of ingredients, and 3. is less than 4. So, the 4-cup bowl is large enough.

Convince Me! Model with Mathematics How many more cups of ingredients could still fit in the bowl? Use a bar diagram and an equation to represent the problem.

Guided Practice

Phillip wants to run a total of 3 miles each day. Monday morning, he ran 1\(\frac{7}{8}\) miles. How many more miles does he still need to run?

Question 1.
Draw a diagram to represent the problem.
Answer:

Bar diagrams show how the quantities in a problem are related.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 72.11

Question 2.
Write and solve an equation for this problem. How did you find the solution?
Answer:

Question 3.
How many more miles does Phillip still need to run?
Answer:

Independent Practice

Model with Math

A landscaper used 2\(\frac{1}{2}\) tons of sunburst pebbles, 3\(\frac{1}{4}\) tons of black polished pebbles, and a ton of river pebbles. What was the total weight of the pebbles?

Question 4.
Draw a diagram and write an equation to represent the problem.
Answer:

Question 5.
Solve the equation. What fraction computations did you do?
Answer:

Question 6.
How many tons of pebbles did the landscaper use?
Answer:

Problem Solving

Performance Task

Camp Activities
During the 6-hour session at day camp, Roland participated in boating, hiking, and lunch. The rest of the session was free time. How much time did Roland spend on the three activities? How much free time did he have?
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.1

Question 7.
Make Sense and Persevere What do you know and what do you need to find?
Answer:

When you model with math, you use the math you know to solve new problems.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.2

Question 8.
Reasoning Describe the quantities and operations you will use to find how much time Roland spent on the planned activities. Which quantities and operations will you use to find how much free time Roland had?
Answer:

Question 9.
Model with Math Draw a diagram and use an equation to help you find how much time Roland spent on the activities. Then, draw a diagram and use an equation to help you find how much free time Roland had.
Answer:

Topic 7 Fluency Practice

Activity

Find a Match

Work with a partner. Point to a clue.
Read the clue.
Look below the clues to find a match. Write the clue letter in the box next to the match.
Find a match for every clue.

Clues
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.6
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.7

Topic 7 Vocabulary Review

Word List

Glossary

Understand Vocabulary

Write always, sometimes, or never.

• benchmark fractions
• common denominator
• equivalent fractions
• mixed number

Question 1.
A fraction can ____ be renamed as a mixed number.
Answer:

Question 2.
The sum of a mixed number and a whole number is ____ a mixed number
Answer:

Question 3.
\(\frac{1}{5}\) is__ used as a benchmark fraction.
Answer:

Question 4.
Equivalent fractions ___ have the same value.
Answer:

For each of these terms, give an example and a non-example.

Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.10

Draw a line from each number in Column A to the same value in Column B.

Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.11

Use Vocabulary in Writing

Question 12.
How can you write a fraction equivalent to \(\frac{60}{80}\) with a denominator that is less than 80?
Answer:

Topic 7 Reteaching

Set A
pages 269-272
Estimate the sum or difference by replacing each fraction with 0, \(\frac{1}{2}\), or 1.
Estimate \(\frac{4}{5}\) + \(\frac{5}{8}\)
Step 1
\(\frac{4}{5}\) is close to 1.
Step 2
\(\frac{5}{8}\) is close to \(\frac{4}{8}\) or \(\frac{1}{2}\)
Step 3
1 + \(\frac{1}{2}\) = 1\(\frac{1}{2}\)
Step 1
\(\frac{7}{12}\) is closes to \(\frac{6}{12}\) or \(\frac{1}{2}\).
Step 2
\(\frac{1}{8}\) is close to 0.
Step 3
\(\frac{1}{2}\) – 0 = \(\frac{1}{2}\)
So, \(\frac{7}{12}\) – \(\frac{1}{8}\) is about \(\frac{1}{2}\).

Remember that you can use as number line to decide if a fraction is closest to 0, \(\frac{1}{2}\), or 1.

Estimate each sum or difference.

Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 88.12

Question 1.
\(\frac{2}{3}\) + \(\frac{5}{6}\)
Answer:

Question 2.
\(\frac{7}{8}\) – \(\frac{5}{12}\)
Answer:

Question 3.
\(\frac{1}{8}\) + \(\frac{1}{16}\)
Answer:

Question 4.
\(\frac{5}{8}\) – \(\frac{1}{6}\)
Answer:

Question 5.
\(\frac{1}{5}\) + \(\frac{1}{3}\)
Answer:

Question 6.
\(\frac{11}{12}\) – \(\frac{1}{10}\)
Answer:

Question 7.
\(\frac{9}{10}\) + \(\frac{1}{5}\)
Answer:

Question 8.
\(\frac{3}{5}\) – \(\frac{1}{12}\)
Answer:

Set B
pages 273-276

Find a common denominator for \(\frac{4}{9}\) and \(\frac{1}{3}\). Then rename each fraction as an equivalent fraction with the common denominator.

Step 1
Multiply the denominators:
9 × 3 = 27, so 27 is a common denominator.
Step 2
Rename the fractions:
\(\frac{4}{9}\) = \(\frac{4}{9}\) × \(\frac{3}{3}\) = \(\frac{4}{9}\)
\(\frac{1}{3}\) = \(\frac{1}{3}\) × \(\frac{9}{9}\) = \(\frac{9}{27}\)
So, \(\frac{4}{9}\) = \(\frac{12}{27}\) and \(\frac{1}{3}\) = \(\frac{9}{27}\).

Remember you can check to see if one denominator is a multiple of the other. Since 9 is a multiple of 3, another common denominator for the fractions and is 9. Find a common denominator. Then rename each fraction as an equivalent fraction with the common denominator.

Question 1.
\(\frac{3}{5}\) and \(\frac{7}{10}\)
Answer:

Question 2.
\(\frac{5}{6}\) and \(\frac{7}{18}\)
Answer:

Question 3.
\(\frac{3}{7}\) and \(\frac{1}{4}\)
Answer:

Set C
pages 277-280, 281-284, 285-288

Find \(\frac{5}{6}\) – \(\frac{3}{4}\)

Step 1
Find a common denominator by listing multiples of 6 and 4.
6:6, 12, 18, 24, 30, 36, 42
4:4, 8, 12, 16, 20, 24, 28, 32
12 is a common multiple of 6 and 4, so use 12 as the common denominator.

Step 2
Use the Identity Property to write equivalent fractions.
\(\frac{5}{6}\) = \(\frac{5 \times 2}{6 \times 2}\) = \(\frac{10}{12}\)
\(\frac{3}{4}\) = \(\frac{3 \times 3}{4 \times 3}\) = \(\frac{9}{12}\)

Step 3
Subtract.
\(\frac{10}{12}\) – \(\frac{9}{12}\) = \(\frac{1}{12}\)

Remember to multiply the numerator and denominator by the same number when writing an equivalent fraction.

Question 1.
\(\frac{2}{5}\) + \(\frac{3}{10}\)
Answer:

Question 2.
\(\frac{1}{9}\) + \(\frac{5}{6}\)
Answer:

Question 3.
\(\frac{3}{4}\) – \(\frac{5}{12}\)
Answer:

Question 4.
\(\frac{7}{8}\) – \(\frac{2}{3}\)
Answer:

Question 5.
\(\frac{1}{12}\) + \(\frac{3}{8}\)
Answer:

Question 6.
\(\frac{4}{5}\) – \(\frac{2}{15}\)
Answer:

Question 7.
Teresa spends \(\frac{1}{3}\) of her day at school. She spends \(\frac{1}{12}\) of her day eating meals. What fraction of the day does Teresa spend at school or eating meals?
Answer:

Set D
pages 289-292

Estimate 5\(\frac{1}{3}\) + 9\(\frac{9}{11}\)
To round a mixed number to the nearest whole number, compare the fraction part of the mixed number to \(\frac{1}{2}\).
If the fraction part is less than \(\frac{1}{2}\), round to the nearest lesser whole number.
5\(\frac{1}{3}\) rounds to 5.
If the fraction part is greater than or equal to \(\frac{1}{2}\), round to the nearest greater whole number.
9\(\frac{9}{11}\) rounds to 10.
So, 5\(\frac{1}{3}\) + 9\(\frac{9}{11}\) ≈ 5 + 10 = 15.

Remember that means ≈ is approximately equal to.”
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 89.1

Remember that you can also use benchmark fractions such as \(\frac{1}{4}\), \(\frac{1}{3}\), \(\frac{1}{2}\), and \(\frac{3}{4}\) to help you estimate.

Estimate each sum or difference.

Question 1.
3\(\frac{1}{4}\) – 1\(\frac{1}{2}\)
Answer:

Question 2.
5\(\frac{2}{9}\) + 4\(\frac{11}{13}\)
Answer:

Question 3.
2\(\frac{3}{8}\) + 5\(\frac{3}{5}\).
Answer:

Question 4.
9\(\frac{3}{7}\) – 6\(\frac{2}{5}\)
Answer:

Question 5.
8\(\frac{5}{6}\) – 2\(\frac{1}{2}\)
Answer:

Question 6.
7\(\frac{3}{4}\) + 5\(\frac{1}{8}\)
Answer:

Question 7.
11\(\frac{5}{12}\) + \(\frac{7}{8}\)
Answer:

Question 8.
13\(\frac{4}{5}\) – 8\(\frac{1}{6}\)
Answer:

Question 9.
A mark on the side of a pier shows the water is 4\(\frac{7}{8}\) feet deep. At high tide, the water level rises 2\(\frac{1}{4}\) feet. About how deep is the water at high tide?
Answer:

Set E
pages 293-296

Find 1\(\frac{1}{4}\) + 1\(\frac{7}{8}\)
Step 1
Rename the fractions with a common denominator. Model the addends and add the fractional parts.
Envision Math Common Core 5th Grade Answer Key Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.1

Step 2
Add the whole numbers to the regrouped fractions.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.2
So, 1\(\frac{1}{4}\) + 1\(\frac{7}{8}\) = 3\(\frac{1}{8}\)

Remember that you may need to rename a fraction as a mixed number.

Use a model to find each sum.

Question 1.
2\(\frac{5}{6}\) + 1\(\frac{5}{6}\)
Answer:

Question 2.
1\(\frac{1}{2}\) + 3\(\frac{3}{4}\)
Answer:

Question 3.
2\(\frac{3}{10}\) + 2\(\frac{4}{5}\)
Answer:

Question 4.
2\(\frac{1}{4}\) + 5\(\frac{11}{12}\)
Answer:

Question 5.
6\(\frac{2}{3}\) + 5\(\frac{5}{6}\)
Answer:

Question 6.
7\(\frac{1}{3}\) + 8\(\frac{7}{9}\)
Answer:

Question 7.
8\(\frac{4}{10}\) + 2\(\frac{3}{5}\)
Answer:

Question 8.
3\(\frac{1}{3}\) + 9\(\frac{11}{12}\)
Answer:

Set F
pages 301-304
Find 2\(\frac{1}{3}\) – 1\(\frac{5}{6}\). Rename 2\(\frac{1}{3}\) as 2\(\frac{2}{6}\)
Step 1
Model the number you are subtracting from, 2\(\frac{1}{3}\) or 2\(\frac{2}{6}\)
Since \(\frac{5}{6}\) > \(\frac{2}{6}\), rename 1 whole as \(\frac{6}{6}\)
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.5
Step 2
Cross out the number you are subtracting, 1\(\frac{5}{6}\).
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.6
The answer is the amount that is left.
So, 2\(\frac{1}{3}\) – 1\(\frac{5}{6}\) = \(\frac{3}{6}\) or \(\frac{1}{2}\)

Remember that the difference is the part of the model that is not crossed out. Use a model to find each difference.

Question 1.
15\(\frac{6}{10}\) – 3\(\frac{4}{5}\)
Answer:

Question 2.
6\(\frac{3}{4}\) – 5\(\frac{1}{2}\)
Answer:

Question 3.
4\(\frac{1}{6}\) – 1\(\frac{2}{3}\)
Answer:

Question 4.
12\(\frac{1}{4}\) – 7\(\frac{1}{2}\)
Answer:

Question 5.
9\(\frac{7}{10}\) – 3\(\frac{4}{5}\)
Answer:

Question 6.
5\(\frac{5}{8}\) – 3\(\frac{1}{4}\)
Answer:

Set G
pages 297-300, 305-308, 309-312

Gil had two lengths of wallpaper, 2\(\frac{3}{4}\) yards and 1\(\frac{7}{8}\) yards long. He used some and now has 1\(\frac{5}{6}\) yards left. How many yards of wallpaper did Gil use?
Step 1
Add to find the total amount of wallpaper Gil had.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.20
Step 2
Subtract to find the amount of wallpaper Gil used.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.21
Gil used 2\(\frac{19}{24}\) yards of wallpaper.

Remember when you add or subtract mixed numbers, rename the fractional parts to have a common denominator.

Solve. Do the operation in the parentheses first.

Question 1.
5\(\frac{1}{2}\) + 2\(\frac{1}{8}\)
Answer:

Question 2.
7\(\frac{5}{6}\) – 3\(\frac{2}{3}\)
Answer:

Question 3.
3\(\frac{1}{4}\) + 1\(\frac{5}{6}\)
Answer:

Question 4.
9 – 3\(\frac{3}{8}\)
Answer:

Question 5.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.22
Answer:

Question 6.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.23
Answer:

Set H
pages 313-316
Think about these questions to help you model with math.
Thinking Habits
• How can I use math I know to help solve this problem?
• How can I use pictures, objects, or an equation to represent the problem?
• How can I use numbers, words, and symbols to solve the problem?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 90.30

Remember that a bar diagram can help you write an addition or a subtraction equation. Draw a bar diagram and write an equation to solve.

Question 1.
Justin jogs 3\(\frac{2}{5}\) miles every morning. He jogs 4\(\frac{6}{10}\) miles every evening. How many miles does he jog every day?
Answer:

Question 2.
Last year Mia planted a tree that was 5\(\frac{11}{12}\) feet tall. This year the tree is 7\(\frac{2}{3}\) feet tall. How many feet did the tree grow?
Answer:

Topic 7 Assessment Practice

Question 1.
Estimate the sum of \(\frac{3}{4}\) and \(\frac{1}{5}\). Write an equation.
Answer:

Question 2.
Select all the expressions that are equal to \(\frac{2}{3}\). Explain.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 100 \(\frac{1}{6}\) + \(\frac{1}{2}\); I found a common denominator and then added the
numerators to get \(\frac{2}{3}\)
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 100 \(\frac{2}{9}\) + \(\frac{7}{18}\); I added the numerators and denominators to get \(\frac{2}{3}\)
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 100 \(\frac{5}{12}\) + \(\frac{1}{4}\); I added the numerators and denominators to get \(\frac{2}{3}\)
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 100 1\(\frac{1}{6}\) – \(\frac{1}{3}\); I found a common denominator and then subtracted the numerators to get \(\frac{2}{3}\)
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 100 2 – 1\(\frac{1}{3}\) found a common denominator and then subtracted the numerators to get \(\frac{2}{3}\)
Answer:

Question 3.
Tim has \(\frac{5}{12}\) of a jar of blackberry jam and \(\frac{3}{8}\) of a jar of strawberry jam. Write \(\frac{5}{12}\) and \(\frac{3}{8}\) using a common denominator. What fraction represents the total amount of jam Tim has?
Answer:

Question 4.
Sandra drove for \(\frac{1}{3}\) hour to get to the store. Then she drove \(\frac{1}{5}\) hour to get to the library. What fraction of an hour did Sandra drive in all? Explain.
Answer:

Question 5.
The bar diagram below shows the fractional parts of a pizza eaten by Pablo and Jamie.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 92.1
A. Rename each fraction using a common denominator.
B. Use the renamed fractions to write and solve an equation to find the total amount of pizza eaten.
Answer:

Question 6.
Choose the correct sum for each expression.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 92.3
Answer:

Question 7.
Benjamin and his sister shared a large sandwich. Benjamin ate of the sandwich and his sister ate of the sandwich.
A. Estimate how much more Benjamin ate than his sister. Explain how you found your estimate.
B. How much more did Benjamin eat than his sister? Find the exact amount.
Answer:

Question 8.
Alicia had 3\(\frac{1}{8}\) feet of wood. She used 1\(\frac{3}{4}\) feet of wood. Estimate the amount of wood Alicia has left.
A. 2 feet
B. 1 foot
C. 0 feet
D. 3 feet
Answer:

Question 9.
Explain why you must rename 2\(\frac{7}{12}\) in order to find 2\(\frac{7}{12}\) – \(\frac{5}{6}\)
Answer:

Question 10.
Mona bought 3\(\frac{3}{8}\) pounds of cheddar cheese. She used 2\(\frac{3}{4}\) pounds to make sandwiches. Write and solve an expression to find how much cheese is left.
Answer:

Question 11.
Marie needs 2\(\frac{1}{4}\) yards of fabric. She already has 1\(\frac{3}{8}\) yards. Which equation shows how many more yards of fabric Marie has to buy?
A. 2\(\frac{1}{4}\) + 1\(\frac{3}{8}\) = 1\(\frac{1}{8}\)
B. \(\frac{1}{4}\) + \(\frac{3}{8}\) = \(\frac{3}{4}\)
C. 2\(\frac{1}{4}\) – 1\(\frac{3}{8}\) = \(\frac{7}{8}\)
D. \(\frac{3}{8}\) – \(\frac{1}{4}\) = \(\frac{1}{8}\)
Answer:

Question 12.
During a trip, Martha drove \(\frac{1}{6}\) of the time, Chris drove \(\frac{1}{4}\) a of the time, and Juan drove the rest of the time. What fraction of the time did Juan drive?
Answer:

Question 13.
Gilberto worked 3\(\frac{1}{4}\) hours on Thursday, 4\(\frac{2}{5}\) hours on Friday, and 6\(\frac{1}{2}\) hours on Saturday. How many hours did he work in all during the three days?
A. 13\(\frac{1}{10}\) hours
B. 13\(\frac{3}{20}\) hours
C. 14\(\frac{1}{10}\) hours
D. 14\(\frac{3}{20}\) hours
Answer:

Question 14.
The model below can be used to find the sum of two mixed numbers. What is the sum? What is the difference? Show your work.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 98.1
Answer:

Question 15.
Estimate the sum of 1\(\frac{1}{3}\) and 2\(\frac{3}{4}\). Explain how you found your estimate.
Answer:

Question 16.
Find 4\(\frac{1}{5}\) – \(\frac{7}{10}\)
A. Explain why 4\(\frac{1}{5}\) must be renamed in order to do the subtraction.
B. Explain how to rename 4\(\frac{1}{5}\) in order to do the subtraction.
Answer:

Question 17.
Mark is making a small frame in the shape of an equilateral triangle with the dimensions shown below. What is the perimeter of the frame?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 99.2
A. 6\(\frac{1}{2}\) cm
B. 9\(\frac{1}{2}\) cm
C. 9\(\frac{1}{6}\) cm
D. 10\(\frac{1}{2}\) cm
Answer:

Question 18.
A baker uses food coloring to color cake batter. He needs 4\(\frac{1}{8}\) ounces of green food coloring. The baker only has 2\(\frac{1}{3}\) ounces. How much more green food coloring does he need? If the baker only finds 1 ounce of food coloring at the store, how many more ounces does the baker need?
Answer:

Question 19.
Models for two mixed numbers are shown below. What is the sum of the numbers? What is the difference? Show your work.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 99.5
Answer:

Question 20.
Dawson says that the expression Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 99.10 is equal to a whole number. Do you agree? Explain.
Answer:

Topic 7 Performance Task

Tying Knots
Liam and Pam each have a length of thick rope. Liam has tied an overhand knot in his rope. The overhand knot is a basic knot often used as a basis for other types of knots.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 99.20

Question 1.
Liam untied the overhand knot. The full length of the rope is shown below. How much rope did the knot use?
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 99.21
Answer:

Question 2.
Liam laid his untied rope end-to-end with Pam’s rope.
Part A
About how long would the two ropes be? Explain how you got your estimate.
Part B
Explain whether the actual length would be greater or less than your estimate.
Answer:

Question 3.
Liam and Pam tied their two ropes together with a square knot. The knot used 15 feet of rope. How long is their rope? Explain.
Envision Math Common Core Grade 5 Answers Topic 7 Use Equivalent Fractions to Add and Subtract Fractions 99.35
Answer:

Question 4.
Marco has a rope that is 16 feet long. He ties his rope to Liam and Pam’s rope with a square knot that uses 1\(\frac{1}{8}\) feet of rope.
Part A
How long are the three ropes tied together? Write an equation to model the problem. Then solve the equation.
Part B
Liam, Pam, and Marco decide to shorten the tied ropes by cutting off \(\frac{2}{5}\) foot from one end and \(\frac{1}{6}\) foot from the other end. About how much rope is cut off in all? Explain.
Part C
How long are the tied ropes now? Show your work.
Answer:

enVision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns

enVision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts: Use Patterns

Go through the enVision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts: Use Patterns regularly and improve your accuracy in solving questions.

enVision Math Common Core 2nd Grade Answers Key Topic 2 Multiplication Facts: Use Patterns

Essential Question:
How can I use what I know about equal groups to help multiply numbers?
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 1

enVision STEM Project: Motion Patterns
Do Research Swings, seesaws, and some other playground objects move with force. Use the Internet or other sources to see what happens when these objects move. Record the number of times that someone pushes or pulls to make the object move. Record the number of times that the object moves.

Journal: Write a Report Include what you found. Also in your report:

  • Explain any patterns you found. Tell how you can use your patterns to predict how the objects will move in the future.
  • Write an equation for one of the patterns.
  • Explain what the numbers in your equation

Review What You Know
• multiplication
• factors
• array
• product

Vocabulary

Choose the best term from the box. Write it on the blank.

Question 1.
The ___ is the answer to a multiplication problem.

Answer:
The product is the answer to a multiplication problem.

Explanation:
In the above-given question,
given that,
there are 4 terms.
they are multiplication, factors, array, and product.
for example:
4 x 3 = 12.
4 and 3 are the factors.
12 is the product.
so the product is the answer to a multiplication problem.

Question 2.
Numbers that are being multiplied are ___.

Answer:
Numbers that are being multiplied are factors.

Explanation:
In the above-given question,
given that,
there are 4 terms.
they are multiplication, factors, array, and product.
for example:
4 x 3 = 12.
where 4 and 3 are factors.
12 is the product.
4 and 3 are being multiplied to get the answer.
so numbers that are being multiplied are factors.

Question 3.
An operation that gives the total when you join equal groups is ____.

Answer:
An operation that gives the total when you join equal groups is an array.

Explanation:
In the above-given question,
given that,
there are 4 terms.
they are multiplication, factors, array, and product.
for example:
5 x 3 = 15.
there are 5 rows.
there are 3 columns.
so an operation that gives the total when you join equal groups is an array.

Multiplication as Repeated Addition

Complete each equation.

Multiplication Facts Use Patterns 1

Question 4.
2 + 2 + 2 + 2 = 4 × ___

Answer:
4 x 2 = 8.

Explanation:
In the above-given question,
given that,
4 groups of 2.
2 + 2 + 2 + 2 = 8.
4 x 2 = 8.

Question 5.
9 + ___ + __ = __ × 9

Answer:
3 x 9 = 27.

Explanation:
In the above-given question,
given that,
3 groups of 9.
9 + 9 + 9 = 27.
3 x 9 = 27.

Question 6.
___ + ___ + ___ + 5 = ___ × 5

Answer:
4 x 5 = 20.

Explanation:
In the above-given question,
given that,
4 groups of 5.
5 + 5 + 5 + 5 = 20.
4 x 5 = 20.

Questfon 7.
2 × 6 = ___ + ___

Answer:
2 x 6 = 12.

Explanation:
In the above-given question,
given that,
2 groups of 6.
6 + 6 = 12.
2 x 6 = 12.

Multiplication on the Number Line

Question 8.
Marty drew this number line.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 10.2
Which multiplication fact does the number line show?
A. 3 × 5 = 15
B. 3 × 4 = 12
C. 3 × 3 = 9
D. 3 × 6 = 18

Answer:
The number line shows the fact 3 x 4 = 12.

Explanation:
In the above-given question,
given that,
In the number line, there are 15 numbers.
the numbers are jumping 3 times.
every time they are jumping 4 numbers.
0 + 4 = 4.
4 + 4 = 8.
8 + 4 = 12.
so 3 x 4 is the correct answer.

Question 9.
Show the multiplication fact on the number line. Write the product. 3 × 2 = ___
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 10.3

Answer:
3 x 2 = 6.

Explanation:
In the above-given question,
given that,
In the number line, there are 8 numbers.
the numbers are jumping 3 times.
every time they are jumping 2 numbers.
0 + 2 = 2.
2 + 2 = 4.
4 + 2 = 6.
so 3 x 2 is the correct answer.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-1

The Commutative Property

Question 10.
How do the arrays represent the Commutative Property of Multiplication?
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 10.4

Answer:
The arrays represents 2 x 6 = 12 and 6 x 2 = 12.

Explanation:
In the above-given question,
given that,
there are 2 rows in the 1st figure.
there are 6 columns in the 2nd figure.
2 x 6 = 12.
there are 6 rows in the 1st figure.
there are 2 columns in the 2nd figure.
6 x 2 = 12.

Pick a Project

PROJECT 2A
How can you make a unique clock tower?
Project: Design a Clock Tower
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 11.1

PROJECT 2B
Who won the College World Series?
Project: Make a Sports Poster and Write a Report
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 11.2

PROJECT 2C
How many are in your crew?
Project: Plan Your Own Race
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 11.3

PROJECT 2D
How many can you sell?
Project: Create a Fundraiser
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 11.4

Lesson 2.1 2 and 5 as Factors

Activity

Solve & Share

Each chicken has 2 legs. How many
You can make sense and persevere in solving the problem by using a number line or a table to record and analyze information.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 11.5
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 11.6

Look Back!
Explain another way you could solve this problem.

Answer:
The number of chickens = 206.

Explanation:
In the above-given question,
given that,
the number of chickens is 2.
each has 2 legs.
2 x 2 = 4.
4 x 2 = 8.
6 x 2 = 12.
8 x 2 = 16.
9 x 2 = 18.
10 x 2 = 20.
12 x 2 = 24.
14 x 2 = 28.
16 x 2 = 32.
18 x 2 = 36.
so the number of legs of a chicken = 206.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-2

Visual Learning Bridge

Essentials Question
How Can You Use Patterns Question to Multiply by 2 and 5?

A.
How many socks are in 7 pairs of socks? How many fingers are on 7 gloves?

You can use doubling to find the number of socks in 7 pairs, 7 + 7 = 14, or you can skip count: 2, 4, 6, 8, 10, 12, 14.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 12.1

Find 7 × 2.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 12.6
There are 14 socks in 7 pairs.

B. Find 7 × 5.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 12.7
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 12.8
You can use skip counting to find the number of fingers on 7 gloves: 5, 10, 15, 20,

Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 12.9
You can also use patterns to find the number of fingers on

1 × 5 = 5
2 × 5 = 10
3 × 5 = 15
4 × 5 = 20
5 × 5 = 25
6 × 5 = 30
7 × 5 = 35

Convince Me!
Use Structure Use doubling, skip counting, or patterns to answer these questions:
How many socks are in 9 pairs? 10 pairs?
How many fingers are on 9 gloves? 10 gloves?

Answer:
Doubling: 9 + 9 = 18 and 10 + 10 = 20.
skip counting: 9 x 5 = 45 and 10 x 5 = 50.
pattern: 9 x 5 = 45 and 10 x 5 = 50.

Explanation:
In the above-given question,
given that,
we can find the socks by using doubling, skip counting, and patterns.
the number of socks in 9 pairs is 9 x 2 = 18.
10 x 2 = 20.
the number of fingers are on 9 gloves = 1 x 2 = 2.
2 x 2 = 4.
3 x 2 = 6.
4 x 2 = 8.
5 x 2 = 10.
6 x 2 = 12.
7 x 2 = 14.
8 x 2 = 16.
9 x 2 = 18.
the fingers on 9 gloves is 9 x 2 = 18.
10 x 2 = 20.

Multiplication Facts Use Patterns 2

Another Example!
Multiples are the products of a number and other whole numbers. Multiples of 2 and 5 have patterns in their products.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 40.1
The products for the 2s facts are multiples of 2.
Multiples of 2 end in 0, 2,4,6, or 8.

Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 40.2
The products for the 5s facts are multiples of 5.
Multiples of 5 end in 0 or 5.

Guided Practice

Do You Understand?

Question 1.
Explain how you can use doubling to find 2 × 8.

Answer:
2 x 8 = 16.

Explanation:
In the above-given question,
given that,
we can use doubling to find 2 x 8 = 16.
8 + 8 = 16.

Question 2.
Bert says 2 × 9 is 19. How can you use patterns to show that Bert’s answer is wrong?

Answer:
Yes, Bert’s answer is wrong.

Explanation:
In the above-given question,
given that,
we can use patterns to find 2 x 9 = 18.
1 x 2 = 2.
2 x 2 = 4.
3 x 2 = 6.
6 x 2 = 12.
7 x 2 = 14.
8 x 2 = 16.
9 x 2 = 18.
so Bert,s answer is wrong.

Do You Know How?

In 3-5, find each product.

Question 3.
2 × 4 = ___
2 × 1 = 2
2 × 2 = 4
2 × 3 = ___
2 × 4 = ___

Answer:
2 x 4 = 8, 2 x 3 = 6.

Explanation:
In the above-given question,
given that,
we can use patterns to find the product.
2 x 1 = 2.
2 x 2 = 4.
2 x 3 = 6.
2 x 4 = 8.

Multiplication Facts Use Patterns 3

Question 4.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 60.3

Answer:
8 x 2 = 16.

Explanation:
In the above-given question,
given that,
we can use patterns to find the product.
2 x 1 = 2.
2 x 2 = 4.
2 x 3 = 6.
2 x 4 = 8.
2 x 5 = 10.
2 x 6 = 12.
2 x 7 = 14.
2 x 8 = 16.
8 x 2 = 16.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-3

Question 5.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 60.4

Answer:
5 x 8 = 40.

Explanation:
In the above-given question,
given that,
we can use patterns to find the product.
5 x 1 = 5.
5 x 2 = 10.
5 x 3 = 15.
5 x 4 = 20.
5 x 5 = 25.
5 x 6 = 30.
5 x 7 = 35.
5 x 8 = 40.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-4

Independent Practice

In 6-12, find the missing product or factor.

Question 6.
2 × 2 = ___

Answer:
The missing product is 4.

Explanation:
In the above-given question,
given that,
2 x 2 = 4.
2 and 2 are the factors.
4 is the product.
so 4 is the missing product.

Question 7.
3 × __ = 15

Answer:
The missing factor is 5.

Explanation:
In the above-given question,
given that,
3 x 5 = 15.
3 and 5 are the factors.
15 is the product.
so the missing factor is 5.

Question 8.
___ × 2 = 14

Answer:
The missing factor is 7.

Explanation:
In the above-given question,
given that,
7 x 2 = 14.
7 and 2 are the factors.
14 is the product.
so the missing factor is 7.

Question 9.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 60.5

Answer:
The missing product is 30.

Explanation:
In the above-given question,
given that,
6 x 5 = 30.
6 and 5 are the factors.
30 is the product.
so 30 is the missing product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-5

Question 10.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 60.6

Answer:
4 x 2 = 8.

Explanation:
In the above-given question,
given that,
4 x 2 = 8.
4 and 2 are the factors.
8 is the product.
4 x 2 = 8.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-6

Multiplication Facts Use Patterns 4

Question 11.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 60.7

Answer:
9 x 2 = 18.

Explanation:
In the above-given question,
given that,
9 x 2 = 18.
9 and 2 are the factors.
18 is the product.
so 18 is the missing product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-7

Question 12.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 60.8

Answer:
5 x 7 = 35.

Explanation:
In the above-given question,
given that,
5 x 7 = 35.
5 and 7 are the factors.
35 is the product.
so 35 is the missing product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-8

Problem Solving

Question 13.
Eric has some nickels. He says they are worth exactly 34 cents. Can you tell if Eric is correct or not? Why or why not?

Answer:
Eric has 1.7 nickels.

Explanation:
In the above-given question,
given that,
Eric has some nickels.
He says they are worth exactly 34 cents.
1 nickel = $0.05 cents.
34 x 0.05 = 1.7.
so Eric was correct.

Question 14.
Critique Reasoning Brian said 78 + 92 + 85 is equal to 300 because each addend is close to 100, and three 100s is the same as 300. Explain why Brian’s reasoning is not reasonable.

Answer:
Brian’s reasoning is not reasonable.

Explanation:
In the above-given question,
given that,
Brian said 78 + 92 + 85 is equal to 300.
78 + 92 = 170.
170 + 85 = 255.
255 is not equal to 300.
so Brian,s reasoning is not reasonable.

Question 15.
Shannon traded 6 nickels for dimes. How many dimes did Shannon receive?

Answer:
The number of dimes did Shannon receive = 12 nickels.

Explanation:
In the above-given question,
given that,
Shannon traded 6 nickels for dimes.
1 dime = 2 nickels.
6 x 2 = 12 nickels.
so the number of dimes did Shannon receive = 12.

Question 16.
enVision® STEM Mike watches how the pendulum swings in his clock. He notices that it swings 1 time every 2 seconds. How long will it take to swing 5 times?

Answer:
The time will it take to swing 5 times = 10 seconds.

Explanation:
In the above-given question,
given that,
Mike watches how the pendulum swings in his clock.
he notices that it swings 1 time every 2 seconds.
1 x 2 = 2.
5 x 2 = 10.
so the time will it take to swing 5 times = 10 seconds.

Question 17.
April has the coins shown below.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 70.1
April counted the value of her coins in cents. List the numbers April would have named.

Answer:
6 x 100 = 100.

Explanation:
In the above-given question,
given that,
April counted the value of her coins in cents.
there are 6 coins.
6 x 100 = 600.
the numbers are 100, 200, 300, 400, 500, and 600.

Question 18.
Higher Order Thinking Jake went bowling. On his first turn, he knocked down 2 pins. On his second turn, he knocked down twice as many pins. So far, how many pins has Jake knocked down? How do you know?

Answer:
The number of pins has Jake knocked down = 6 pins.

Explanation:
In the above-given question,
given that,
Jake went bowling.
on his 1st turn, he knocked down 2 pins.
on his second turn, he knocked down twice as many pins.
2 + 4 = 6.
so the number of pins has Jake knocked down = 6.

Assessment Practice

Question 19.
Mary Beth drew 4 pentagons. How many sides are on all 4 of Mary Beth’s pentagons?
A. 10
B. 15
C. 20
D. 25

Answer:
The number of sides on all 4 of Mary Beth,s pentagons = 20.

Explanation:
In the above-given question,
given that,
Mary Beth drew 4 pentagons.
Pentagon has 5 sides.
5 + 5 + 5 + 5 = 20.
so the number of sides on all 4 of pentagons = 20.

Question 20.
Carmen has 6 pairs of shoes. How many individual shoes does Carmen have?
A. 6
B. 8
C. 10
D. 12

Answer:
Option D is the correct answer.

Explanation:
In the above-given question,
given that,
Carmen has 6 pairs of shoes.
6 + 6 = 12.
6 x 2 = 12.
so option D is correct.

Lesson 2.2 9 as a Factor

Activity

Solve & Share

Maria bought 4 packages of bottled water. There are 9 bottles in each package. How many bottles did Maria buy? Explain how you solved this problem.

Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 50.3
An array or a data table can help you construct arguments.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 50.4

Answer:
The number of bottles Maria bought = 28.

Explanation:
In the above-given question,
given that,
Maria bought 4 packages of bottled water.
There are 9 bottles in each package.
1 x 9 = 9.
2 x 9 = 18.
3 x 7 = 21.
4 x 7 = 28.
so the number of bottles Maria bought = 28.

Look Back!
If Maria bought 9 packages of bottled water and there were 4 bottles in each package, would the number of bottles she bought be the same or different? Explain.

Answer:
The number of bottles Maria bought = 36.

Explanation:
In the above-given question,
given that,
Maria bought 9 packages of bottled water.
There are 4 bottles in each package.
1 x 4 = 4.
2 x 4 = 8.
3 x 4 = 12.
4 x 4 = 16.
5 x 4 = 20.
6 x 4 = 24.
7 x 4 = 28.
8 x 4 = 32.
9 x 4 = 36.
so the number of bottles Maria bought = 36.

Visual Learning Bridge

Essential Question
How Can Patterns Be Used to Find 9s Facts?
A.
Nine roses were put in each package for sale at the Florida Botanical Garden’s annual gift and plant sale. How many roses are in 8 packages?
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 50.5
9s Facts
0 × 9 = 0
1 × 9 = 9
2 × 9 = 18
3 × 9 = 27
4 × 9 = 36
5 × 9 = 45
6 × 9 = 54
7 × 9 = 63
8 × 9 = Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 70
9 × 9 = Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 70
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 50.6
To find the next multiple of 9 in the table, you can add ten and then subtract I.

Answer:
The number of roses in 8 packages = 72.

Explanation:
In the above-given question,
given that,
Nine roses were put in each package for sale at the Florida Botanical Garden’s annual gift and plant sale.
9 x 8 = 72.
9 x 9 = 81.
72 + 10 = 82.
82 – 1 = 81.
so the number of roses in 8 packages = 72.

B.
One Way
Start with 1 × 9 = 9.
When you add ten:
Increase the tens place by 1.
When you subtract 1:
Decrease the one’s place by 1.
2 × 9 = 18
3 × 9 = 27
4 × 9 = 36
5 × 9 = 45
6 × 9 = 54
7 × 9 = 63
8 × 9 = 72

Multiplication Facts Use Patterns 5

C.
Another Way
Start with 0.
For each group of 9:
Add 1 ten and subtract 1 one.
For 8 groups of 9:
Add 8 tens and subtract 8 ones.
8 × 9 = 8 tens – 8 ones
8 × 9 = 80 – 8
8 × 9 = 72
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 70.9
There are 72 roses in 8 packages.

Convince Me!
Use Structure Use the patterns above to find 9 × 9. Explain how you found the product.

Answer:
9 x 9 = 81.

Explanation:
In the above-given question,
given that,
there are 81 roses in 9 packages.
A. 9 x 9 = 81.
9 x 10 = 90.
81 + 10 = 91.
91 – 1 = 90.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
5 x 9 = 45.
6 x 9 = 54.
7 x 9 = 63.
8 x 9 = 72.
9 x 9 = 81.
C. 9 tens – 9 ones.
90 – 9 = 81.
9 x 9 = 81.

Guided Practice

Do You Understand?

Question 1.
Paul thinks 3 × 9 is 24. Use a 9s pattern to show Paul is wrong.

Answer:
Paul was wrong.

Explanation:
In the above-given question,
given that,
A. 3 x 9 = 27.
3 x 10 = 30.
27 + 10 = 37.
37 – 7 = 30.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
C. 3 tens – 9 ones.
30 – 9 = 21.
3 x 9 = 27.

Question 2.
Look at the table of 9s facts on the previous page. Describe a number pattern in the multiples of 9.

Answer:
9 x 9 = 81.

Explanation:
In the above-given question,
given that,
A. 9 x 9 = 81.
9 x 10 = 90.
81 + 10 = 91.
91 – 1 = 90.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
5 x 9 = 45.
6 x 9 = 54.
7 x 9 = 63.
8 x 9 = 72.
9 x 9 = 81.
C. 9 tens – 9 ones.
90 – 9 = 81.
9 x 9 = 81.

Do You Know How?

In 3-10, find each product.

Question 3.
9 × 2 = ___

Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 63.1
You can use patterns to solve multiplication facts with 9s.

Answer:
9 x 2 = 18.

Explanation:
In the above-given question,
given that,
A. 9 x 2 = 18.
B. 9 x 2 = 18.
9 x 3 = 27.
18 + 10 = 28.
28 – 10 = 18.
C. 9 tens – 2 ones.
9 x 10 – 2 x 1.
90 – 2 = 18.

Question 4.
___ = 5 × 9

Answer:
5 x 9 = 45.

Explanation:
In the above-given question,
given that,
A. 5 x 9 = 45.
B. 5 x 10 = 50.
45 + 10 = 55.
55 – 10 = 45.
C. 5 tens – 5 ones.
50 – 5 = 45.

Question 5.
7 × 9 = ___

Answer:
7 x 9 = 63.

Explanation:
In the above-given question,
given that,
A. 7 x 9 = 63.
7 x 10 = 70.
63 + 10 = 73.
73 – 3 = 60.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
5 x 9 = 45.
6 x 9 = 54.
7 x 9 = 63.

Question 6.
__ = 4 × 9

Answer:
4 x 9 = 36.

Explanation:
In the above-given question,
given that,
A. 4 x 9 = 36.
4 x 10 = 40.
36 + 10 = 46.
46 – 6 = 40.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
C. 4 tens – 9 ones.
40 – 9 = 36.
4 x 9 = 36.

Question 7.
2 × 9 = ___

Answer:
2 x 9 = 18.

Explanation:
In the above-given question,
given that,
A. 2 x 9 = 18.
2 x 10 = 20.
20 – 2 = 18.
B. 1 x 9 = 9.
2 x 9 = 18.
C. 2 tens – 9 ones.
20 – 9 = 18.
2 x 9 = 18.

Question 8.
___ = 6 × 9

Answer:
6 x 9 = 54.

Explanation:
In the above-given question,
given that,
A. 6 x 9 = 54.
6 x 10 = 60.
54 + 10 = 64.
64 – 10 = 54.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
5 x 9 = 45.
6 x 9 = 54.
C. 6 tens – 9 ones.
60 – 6 = 54.

Question 9.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 65.1

Answer:
3 x 9 = 27.

Explanation:
In the above-given question,
given that,
by using patterns we can solve in three models.
A. 3 x 9 = 27.
3 x 10 = 30.
27 + 10 = 37.
37 – 10 = 27.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
C. 3 tens – 9 ones.
30 – 3 = 27.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-9

Question 10.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 65.2

Answer:
8 x 9 = 72.

Explanation:
In the above-given question,
given that,
by using patterns we can solve in 3 methods.
A. 8 x 9 = 72.
8 x 10 = 80.
72 + 10 = 82.
82 – 2 = 80.
B. 1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
5 x 9 = 45.
6 x 9 = 54.
7 x 9 = 63.
8 x 9 = 72.
C. 8 tens – 9 ones.
80 – 9 = 72.
8 x 9 = 72.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-10

Independent Practice

In 11-22, find the missing product or factor.

Question 11.
9 × 0 = ___

Answer:
The missing product = 0.

Explanation:
In the above-given question,
given that,
9 x 0 = 0.
0 and 9 are the factors.
9 x 0 = 0.

Question 12.
2 × ___ = 18

Answer:
The missing factor is 9.

Explanation:
In the above-given question,
given that,
2 x 9 = 18.
2 and 9 are the factors.
18 is the product.
so the missing factor is 9.

Question 13.
___ × 9 = 72

Answer:
The missing factor is 8.

Explanation:
In the above-given question,
given that,
8 x 9 = 72.
8 and  9 are the factors.
72 is the product.
so the missing factor is 8.

Question 14.
9 × 9 = ___

Answer:
The missing product is 81.

Explanation:
In the above-given question,
given that,
9 x 9 = 81.
the factors are 9 and 9.
81 is the product.
so the missing product is 81.

Question 15.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 66.1

Answer:
The missing product is 36.

Explanation:
In the above-given question,
given that,
4 x 9 = 36.
4 and 6 are the factors.
36 is the product.
so the missing product is 36.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-11

Question 16.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 66.2

Answer:
The missing product is 45.

Explanation:
In the above-given question,
given that,
9 x 5 = 45.
9 and 5 are the factors.
45 is the product.
so the missing product is 45.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-12

Question 17.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 66.3

Answer:
The missing product is 63.

Explanation:
In the above-given question,
given that,
9 x 7 = 63.
9 and 7 are the factors.
63 is the missing product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-13

Question 18.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 66.4

Answer:
The missing product is 9.

Explanation:
In the above-given question,
given that,
9 x 1 = 9.
9 and 1 are the factors.
9 is the product.
so the missing product is 9.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-14

Question 19.
What is 9 × 3? ___

Answer:
The missing product is 27.

Explanation:
In the above-given question,
given that,
9 x 3 = 27.
9 and 3 are the factors.
27 is the product.
so the missing product is 27.

Question 20.
What is 9 × 6? ____

Answer:
The missing product is 54.

Explanation:
In the above-given question,
given that,
9 x 6 = 54.
9 and 6 are the factors.
54 is the product.
so the missing product is 54.

Question 21.
What is 0 × 9? ___

Answer:
The missing product is 0.

Explanation:
In the above-given question,
given that,
0 x 9 = 0.
9 is the factor.
0 is the product.
so the missing product is 0.

Question 22.
What is 9 × 8? ____

Answer:
The missing product is 72.

Explanation:
In the above-given question,
given that,
9 x 8 = 72.
9 and 8 are the factors.
72 is the product.
so the missing product is 72.

Problem Solving

In 23-25, use the table to the right.

Question 23.
Reasoning The library is having a used book sale. How much do 4 hardcover books cost? Draw a number line to show the
answer.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 69.1

Answer:
The cost of 4 hardcover books = $ 36.

Explanation:
In the above-given question,
given that,
The library is having a used book sale.
the hardcover book cost $9.
9 x 4 = 36.
9 + 9 + 9 + 9 = 36.
so the cost of 4 hardcover books = $36.

Question 24.
Higher Order Thinking How much more would Chico spend if he bought 3 hardcover books rather than 3 paperback books? Show how you found the answer.

Answer:
The money would Chico spends = $12.

Explanation:
In the above-given question,
given that,
chico spend if he bought 3 hardcover books rather than 3 paperback books.
1 hardcover book = $9.
3 hardcover books =27.
9 + 9 + 9 = $27.
1 paper back book = $5.
3 paperback books = $15.
5 + 5 + 5 = 15.
27 – 15 = 12.
so the money would Chico spend = $12.

Question 25.
Maggie bought only magazines. The clerk told her she owed $15. How does Maggie know the clerk made a mistake?

Answer:
Maggie was not correct.

Explanation:
In the above-given question,
given that,
Maggie bought only magazines.
the clerk told her she owed $15.
maggie bought magazines for $2.
2 + 2 + 2 + 2 + 2 + 2 + 2 = 14.

Question 26.
The owner of a flower shop put 9 sunflowers in each of 6 vases. Then he counted the flowers by 9s. List the numbers he named.
Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 69.2

Answer:
The numbers of sunflowers are 54.

Explanation:
In the above-given question,
given that,
The owner of a flower shop put 9 sunflowers in each of 6 vases.
Then he counted the flowers by 9s.
1 x 9 = 9.
2 x 9 = 18.
3 x 9 = 27.
4 x 9 = 36.
5 x 9 = 45.
6 x 9 = 54.
so the number of sunflowers is 54.

Question 27.
Number Sense Chris and Jerome played a video game. Chris scored 437 points. Jerome scored 398 points. Who scored more points? Explain your answer using >,<, or =

Answer:
Chris > Jerome.

Explanation:
In the above-given question,
given that,
Chris and Jerome played a video game.
Chris scored 437 points.
Jerome scored 398 points.
437 > 398.
so Chris is greater than Jerome.
Chris > Jerome.

Assessment Practice

Question 28.
Sarah planted 2 groups of 9 sabal palm trees. How many palm trees did Sarah plant?
A. 9
B. 18
C. 27
D. 36

Answer:
Option B is correct.

Explanation:
In the above-given question,
given that,
Sarah planted 2 groups of 9 sabal palm trees.
2 groups of 9.
9 + 9 = 18.
2 x 9 = 18.
so 18 is the correct answer.

Question 29.
Corky breaks her route from Orlando to Tampa into 9 lengths of 9 miles each. How many miles is it from Orlando to Tampa?
A. 9
B. 27
C. 72
D. 81

Answer:
The number of miles from Orlando to Tampa is 81 miles.

Explanation:
In the above-given question,
given that,
Corky breaks her route from Orlando to Tampa into 9 lengths of 9 miles each.
9 x 9 = 81.
9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 + 9 = 81.
so the number of miles from Orlando to Tampa is 81 miles.

Lesson 2.3 Apply Properties: Multiply by 0 and 1

Activity

Solve & Share

Carlos said that 6 times 0 equals 6. Do you agree? Explain your thinking.

Envision Math Common Core Grade 3 Answer Key Topic 2 Multiplication Facts Use Patterns 72.1
Be precise.
What does it mean to multiply something by zero?

Look Back!
Draw a picture to show 5 × 0 = 0.

Visual Learning Bridge

Essential Question
What Are the Patterns in Multiples of 1 and 0?

A.
Kira has 8 plates with 1 orange on each plate. How many oranges does Kira have?

You can use patterns to find 8 × 1.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 73.1
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 73.2

B. 8 groups with 1 in each group equal 8 in all.
8 × 1 = 8
Kira has 8 oranges.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 105
1 plate with 8 oranges also equals 8 oranges.
1 × 8 = 8
The Identity (One) Property of Multiplication: When you multiply a number by 1, the product is that number.

C. If Kira has 4 plates with O oranges on each plate, she has 0 oranges.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 73.3
4 × 0 = 0
If 4 × 0 = 0, then 0 × 4 = 0.
The Zero Property of Multiplication: When you multiply a number by 0, the product is 0.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 73.5

Convince Me!
Use Appropriate Tools How would you use counters to show 7 × 1? How many counters would you have in all?

Guided Practice

Do You Understand?

Question 1.
Draw a number line to show 8 × 1 = 8.

Answer:
8 x 1 = 8.

Explanation:
In the above-given question,
given that,
Kira has 8 plates with 1 orange on each plate.
we can use patterns to find 8 x 1.
8 x 1 = 8.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-15

Question 2.
Chad has 6 plates. Each plate has 1 apple and 0 grapes. How many apples are there? How many grapes are there?
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 106

Answer:
The number of apples = 6.
The number of grapes = 0.

Explanation:
In the above-given question,
given that,
Chad has 6 plates.
each plate has 1 apple and 0 grapes.
we can use patterns to find apples and grapes.
6 x 1 = 6.
chad has 6 apples.
1 plate with 6 apples also equals 6 apples.
1 x 6 = 6.
Chad has 6 plates with 0 grapes on each plate, she has 0 oranges.
6 x 0 = 0.
0 x 6 = 6.
so the number of apples is 6.
the number of grapes is 0.

Do You Know How?

In 3-8, find each product.

Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.1
You can use the Identity and Zero Properties of Multiplication to find these products.

Question 3.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.2
3 × 1 = ___

Answer:
The product is 3.

Explanation:
In the above-given question,
given that,
3 x 1 = 3.
the factors are 3 and 1.
product is 3.
we can use the identity and zero properties of multiplication.
3 x 1 = 3.
3 x 0 = 0.

Question 4.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.3
3 × 0 = ___

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
3 x 0 = 0.
3 is the factor.
here we can apply the zero property of multiplication.
we are multiplying the 3 with 0.
3 x 0 = 0.

Question 5.
1 × 7 = __

Answer:
The product is 7.

Explanation:
In the above-given question,
given that,
1 x 7 = 7.
1 and 7 are the factors.
here we can apply the identity property of multiplication.
we are multiplying 7 with 1.
so the product is 7.

Question 6.
__ = 5 × 0

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
5 x 0 = 0.
5 is the factor.
here we can apply the zero property of multiplication.
we are multiplying the 5 with 0.
5 x 0 = 0.

Question 7.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.4

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
4 x 0 = 0.
4 is the factor.
here we can apply the zero property of multiplication.
we are multiplying the 4 with 0.
so the product is 0.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-16

Question 8.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.5

Answer:
The product is 2.

Explanation:
In the above-given question,
given that,
2 x 1 = 2.
1 and 2 are the factors.
here we can apply the identity property of multiplication.
we are multiplying 2 with 1.
so the product is 2.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-17

Independent Practice

In 9-15, find each product.

Question 9.
0 × 4 = ___

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
4 x 0 = 0.
4 is the factor.
here we can apply the zero property of multiplication.
we are multiplying the 4 with 0.
so the product is 0.

Question 10.
__ = 1 × 6

Answer:
The product is 6.

Explanation:
In the above-given question,
given that,
1 x 6 = 6.
1 and 6 are the factors.
here we can apply the identity property of multiplication.
we are multiplying 6 with 1.
so the product is 6.

Question 11.
4 × 1 = ___

Answer:
The product is 4.

Explanation:
In the above-given question,
given that,
1 x 4 = 4.
1 and 4 are the factors.
here we can apply the identity property of multiplication.
we are multiplying 4 with 1.
so the product is 4.

Question 12.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.6

Answer:
The product is 9.

Explanation:
In the above-given question,
given that,
1 x 9 = 9.
1 and 9 are the factors.
here we can apply the identity property of multiplication.
we are multiplying 9 with 1.
so the product is 9.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-18

Question 13.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.7

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
2 x 0 = 0.
2 is the factor.
here we can apply the zero property of multiplication.
we are multiplying the 2 with 0.
so the product is 0.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-19

Question 14.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.8

Answer:
The product is 1.

Explanation:
In the above-given question,
given that,
1 x 1 = 1.
1 and 1 are the factors.
here we can apply the identity property of multiplication.
we are multiplying 1 with 1.
so the product is 1.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-20

Question 15.
Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 82.9

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
6 x 0 = 0.
6 is the factor.
here we can apply the zero property of multiplication.
we are multiplying the 6 with 0.
so the product is 0.
Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-20

In 16-21, write <, >, or = in each Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 to compare.

Question 16.
1 × 6 Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 8 × 0

Answer:
1 x 6 > 8 x 0.

Explanation:
In the above-given question,
given that,
any number if we multiply by 1 we will get that number.
1 x 6 = 6.
Any number if we multiply by 0 we will get 0.
8 x 0 = 0.
6 is greater than 0.
6 > 0.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-21

Question 17.
0 × 6 Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 6 × 0

Answer:
0 x 6 = 6 x 0.

Explanation:
In the above-given question,
given that,
Any number if we multiply by 0 we will get 0.
0 x 6 = 0.
6 x 0 = 0.
0 is equal to 0.
0 = 0.

Question 18.
0 × 7 Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 5 × 1

Answer:
0 x 7 < 5 x 1.

Explanation:
In the above-given question,
given that,
Any number if we multiply by 0 we will get 0.
0 x 7 = 0.
any number if we multiply by 1 we will get that number.
5 x 1 = 5.
0 x 7 < 5 x 1.
0 < 5.

Question 19.
0 × 0 Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 0 × 9

Answer:
0 x 0 = 0 x 9.

Explanation:
In the above-given question,
given that,
Any number if we multiply by 0 we will get 0.
0 x 0 = 0.
0 x 9 = 0.
0 is equal to 0.
0 = 0.

Question 20.
1 × 7 Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 5 × 1

Answer:
1 x 7 > 5 x 1.

Explanation:
In the above-given question,
given that,
Any number if we multiply by 1 we will get that number.
1 x 7 = 7.
any number if we multiply by 1 we will get that number.
5 x 1 = 5.
1 x 7 > 5 x 1.
7 > 5.

Question 21.
1 × 4 Envision Math Common Core 3rd Grade Answers Topic 2 Multiplication Facts Use Patterns 83 4 × 1

Answer:
1 x 4 = 4 x 1.

Explanation:
In the above-given question,
given that,
Any number if we multiply by 1 we will get that number.
1 x 4 = 4.
any number if we multiply by 1 we will get that number.
4 x 1 = 4.
1 x 4 = 4 x 1.
4 = 4.

Problem Solving

Question 22.
Brent drew this model to show that 5 groups of 1 is the same as 1 group of 5. Is Brent correct? Explain how you know.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 83.1

Answer:
Yes, Brent was correct.

Explanation:
In the above-given question,
given that,
brent drew 5 groups of 1 model in ist figure.
5 x 1 = 5.
any number multiplied by 1 we will get the same number.
brent drew 1 group of 5 models in the 2nd figure.
1 x 5 = 5.
if we multiply by 1 we will get the same number.
so brent was correct.

Question 23.
Make Sense and Persevere A unicycle relay team has 4 riders. Each rider has one unicycle. If each unicycle has 1 wheel, how many wheels does the team have? What property of multiplication can you use to find the answer?

Answer:
The number of wheels does the team has = 4 wheels.

Explanation:
In the above-given question,
given that,
a unicycle relay team has 4 riders.
each rider has one unicycle.
if each unicycle has 1 wheel.
we use the identity property to find the answer.
4 x 1 = 4.
1 x 4 = 4.
so the number of wheels does the team has = 4 wheels.

Question 24.
Tickets for a school concert are free for students. The cost is $1 for each adult. What is the total cost of tickets for 5 students?

Answer:
The total cost of tickets for 5 students = $5.

Explanation:
In the above-given question,
given that,
tickets for a school concert are free for students.
the cost is $1 for each adult.
1 x 5 = 5.
5 x 1 = 5.
so the total cost of tickets for 5 students = $5.

Question 25.
Higher Order Thinking The product of two factors is 0. One of the factors is 0. Can you tell what the other factor is? Explain your answer.

Answer:
The other factor is 5.

Explanation:
In the above-given question,
given that,
The product of the two factors is 0.
one of the factors is 0.
for example:
5 x 0 = 0.
the factors are 5 and 0.
if we multiply the number by 0 we will get the product is 0.
so the other factor is 5.

Question 26.
The children in the third-grade classes are having a bike parade. Barb’s class has 18 bikes. Tim’s class has some rows of bikes with 5 bikes in each row. Tim’s class has more bikes than Barb’s class. How many rows of bikes could Tim’s class have? Explain.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 87.1

Answer:
The number of rows of bikes could Tim’s class have = 4 rows.

Explanation:
In the above-given question,
given that,
the children in the third-grade classes are having a bike parade.
Barb’s class has 18 bikes.
tim’s class has some rows of bikes with 5 bikes in each row.
5 x 4 = 20.
5 + 5 + 5 + 5 + 5 = 20.
so the number of rows of bikes could Tim’s class have = 4 rows.

Assessment Practice

Question 27.
Use the Zero Property of Multiplication and the Identity Property of Multiplication to select all the correct equations.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 1 × 4 = 1
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 4 × 4 = 0
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 7 × 1 = 7
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 0 × 9 = 9
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 0 × 1 = 0

Answer:
7 x 1 = 7.
0 x 1 = 0.

Explanation:
In the above-given question,
given that,
zero property of multiplication is we will get 0.
0 x 1 = 0.
identity property of multiplication is we will get that number.
7 x 1 = 7.
so 7 x 1 = 7 and 0 x 1 = 0 is correct.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-22

Question 28.
Use the Zero Property of Multiplication and the Identity Property of Multiplication to select all the correct equations.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 0 × 0 = 0
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 1 × 3 = 3
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 6 × 1 = 6
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 0 × 4 = 0
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88 1 × 1 = 0

Answer:
0 x 0 = 0, 0 x 4 = 0, 1 x 3 = 3, and 6 x 1 = 6.

Explanation:
In the above-given question,
given that,
In zero property if we multiply by 0 we will get 0.
0 x 0 = 0,  x 4 = 0.
if we multiply by 1 we will get the same number.
1 x 3 = 3, and 6 x 1 = 6.
so 0 x 0 = 0, 0 x 4 = 0, 1 x 3 = 3, and 6 x 1 = 6.

Lesson 2.4 Multiply by 10

Activity

Solve & Share

Duke runs 10 miles each week. How many miles will he run in 6 weeks? 7 weeks? 8 weeks? Describe patterns you find.

Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 88.1
You can generalize. What repeats in this problem?

Answer:
6 weeks = 60 miles.
7 weeks = 70 miles.
8 weeks = 80 miles.

Explanation:
In the above-given question,
given that,
Duke runs 10 miles each week.
6 weeks = 6 x 10 = 60.
7 weeks = 7 x 10 = 70.
8 weeks = 8 x 10 = 80.

Look Back!
How are the patterns when multiplying by 10 related to the patterns when multiplying by 5?

Answer:
The patterns when multiplying by 10 are double the pattern when we multiply by 5.

Explanation:
In the above-given question,
given that,
if we multiply by 5 we will get,
6 x 5 = 30.
7 x 5 = 35.
8 x 5 = 40.
if we multiply by 10 we will get,
6 x 10 = 60.
7 x 10 = 70.
8 x 10 = 80.

Visual Learning Bridge

Essential Question
What Are the Patterns Question in Multiples of 10?

A.
Greg wants to train for a race that is 10 weeks away. The chart shows his training schedule. How many miles will Greg each swim, run, and bike to train for the race?
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.1
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.2
You can use place value to find multiples of 10.

B.
Use place-value blocks.
Find 4 × 10.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.3
4 × 10 is 4 groups of 10, or 40. 40 is ten times greater than 4. Greg will swim 40 miles.
Find 10 × 10.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.4
10 × 10 is 10 groups of 10, or 100. 100 is ten times greater than 10. Greg will run 100 miles.

C. Use place-value patterns.
When you multiply a number by 10, the number tells you what to record in the tens place. Find 9 × 10.
1 × 10 = 10
2 × 10 = 20
3 × 10 = 30
4 × 10 = 40
5 × 10 = 50
6 × 10 = 60
7 × 10 = 70
8 × 10 = 80
9 × 10 = 90

9 × 10 is 9 groups of 10, or 90. Greg will bike 90 miles.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.5

Convince Me!
Use Structure Greg also walks 5 miles each week for the 10 weeks of his training. How many miles did Greg walk while training? Write an equation, and explain how to use a pattern to find the product.

Answer:
The number of miles did Greg walk while training = 50.

Explanation:
In the above-given question,
given that,
Greg also walks 5 miles each week for the 10 weeks of his training.
5 groups of 10.
10 x 5 = 50.
1 x 10 = 10.
2 x 10 = 20.
3 x 10 = 30.
4 x 10 = 40.
5 x 10 = 50.
so the number of miles did Greg walk while training = 50.
50 is ten times greater than 5.

Another Example!
You can use a number line to find 3 × 10.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.6
30 is 3 groups of 10. 30 is ten times greater than 3.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 89.7

Guided Practice

Do You Understand?

Question 1.
How can you use place value to find 9 × 10?

Answer:
When you multiply a number by 10, the number tells you what to record in the tens place.

Explanation:
In the above-given question,
given that,
1 × 10 = 10.
2 x 10 = 20.
3 x 10 = 30.
4 x 10 = 40.
5 x 10 = 50.
6 x 10 = 60.
7 x 10 = 70.
8 x 10 = 80.
9 x 10 = 90.

Question 2.
If you multiply any one-digit number by 10, what do you write in the tens digit of the product?

Answer:
If we multiply 5 by 10, we will get the same number in the tens digit.

Explanation:
In the above-given question,
given that,
1 x 10 = 10.
2 x 10 = 20.
3 x 10 = 30.
4 x 10 = 40.
5 x 10 = 50.
if we multiply  5 by 10, we will get the same number in the tens digit.
5 groups of 10.
5 x 10 = 50.

Do You Know How?

In 3-6, find each product.

Question 3.
2 × 10 = ___0

Answer:
The product is 20.

Explanation:
In the above-given question,
given that,
2 x 10 = 20.
if we multiply by 10 we get the same number in the tens digit.
the factors are 2 and 10.
the product is 20.

Question 4.
6 × 10 = ___ 0

Answer:
The product is 60.

Explanation:
In the above-given question,
given that,
6 x 10 = 60.
if we multiply by 10 we get the same number in the tens digit.
the factors are 6 and 10.
the product is 60.

Question 5.
8 × 10 = __

Answer:
The product is 80.

Explanation:
In the above-given question,
given that,
8 x 10 = 20.
if we multiply by 10 we get the same number in the tens digit.
the factors are 8 and 10.
the product is 80.

Question 6.
9 × 10 = __

Answer:
The product is 90.

Explanation:
In the above-given question,
given that,
9 x 10 = 90.
if we multiply by 10 we get the same number in the tens digit.
the factors are 9 and 10.
the product is 90.

Independent Practice

In 7 and 8, use the number lines to help find the product.

Question 7.
1 × 10 = ___
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 90.1

Answer:
The product is 10.

Explanation:
In the above-given question,
given that,
in the given number line they gave the 5 numbers.
they are 0, 10, 20, 30, 40, and 50.
1 x 10 = 10.
so we jump one time in the number line.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-23

Question 8.
5 × 10 = __
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 130

Answer:
The product is 50.

Explanation:
In the above-given question,
given that,
in the given number line they gave the 5 numbers.
they are 0, 10, 20, 30, 40, and 50.
5 x 10 = 50.
so we jump five times in the number line.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-24

In 9-14, find the missing product or factor.

Question 9.
10 × 2 = __ 0

Answer:
The missing product is 20.

Explanation:
In the above-given question,
given that,
10 x 2 = 20.
if we multiply by 10 we get the same number in the tens digit.
the factors are 2 and 10.
so the missing product is 20.

Question 10.
9 × 10 = __ 0

Answer:
The missing product is 90.

Explanation:
In the above-given question,
given that,
10 x 9 = 90.
if we multiply by 10 we get the same number in the tens digit.
the factors are 9 and 10.
so the missing product is 90.

Question 11.
7 × 10 = __ 0

Answer:
The missing product is 70.

Explanation:
In the above-given question,
given that,
10 x 7 = 70.
if we multiply by 10 we get the same number in the tens digit.
the factors are 7 and 10.
so the missing product is 70.

Question 12.
3 × 10 = __

Answer:
The missing product is 30.

Explanation:
In the above-given question,
given that,
10 x 3 = 30.
if we multiply by 10 we get the same number in the tens digit.
the factors are 3 and 10.
so the missing product is 30.

Question 13.
5 × __ = 50

Answer:
The missing factor is 10.

Explanation:
In the above-given question,
given that,
10 x 5 = 50.
if we multiply by 10 we get the same number in the tens digit.
the factors are 5 and 10.
so the missing factor is 10.

Question 14.
80 = 10 × ___

Answer:
The missing factor is 8.

Explanation:
In the above-given question,
given that,
10 x 8 = 80.
if we multiply by 10 we get the same number in the tens digit.
the factors are 8 and 10.
so the missing factor is 8.

Problem Solving

Question 15.
Reasoning Eddie borrowed $65 from his dad. Every month, he pays back $12. Complete the table to find how much money Eddie still owes his dad after 4 months.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 90.4

Answer:
The money Eddie still owes his dad after 4 months = $ 48.

Explanation:
In the above-given question,
given that,
Eddie borrowed $65 from his dad.
Every month, he pays back $12.
he paid for 4 months.
they are April, May, June, and July.
12 + 12 + 12 + 12 = 48.
12 x 4 = 48.
so the money Eddie still owes his dad after 4 months = $48.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-25

Question 16.
Kimmy bought 7 tickets to a concert. Each ticket costs $10. She also paid $5 to have the tickets delivered. Write equations to show how much money Kimmy spent in all.

Answer:
The money Kimmy spent in all = $105.

Explanation:
In the above-given question,
given that,
Kimmy bought 7 tickets to a concert.
Each ticket costs $10.
7 x 10 = 70.
10 + 10 + 10 + 10 + 10 + 10 + 10 = 70.
she also paid $5 to have the tickets delivered.
7 x 5 = 35.
5 + 5 + 5 + 5 + 5 + 5 + 5 = 35.
70 + 35 = 105.
so the money Kimmy spent in all = $105.

Question 17.
Write an addition equation and a multiplication equation for the array below.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 90.5

Answer:
3 x 5 = 15.
5 + 5 + 5 = 15.

Explanation:
In the above-given question,
given that,
there are 3 rows in the figure.
there are 5 columns in the figure.
3 x 5 = 15.
3 + 3 + 3 + 3 + 3 = 15.

Question 18.
Use the table to find the total number of juice boxes bought for a school picnic.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 90.6
Juice boxes: ____

Answer:
The total number of juice boxes bought for a school picnic = 70.

Explanation:
In the above-given question,
given that,
students bought 3 different food items for a picnic.
some of the students bought 8 packages of hot dogs.
each package contains 10 hot dogs.
some of the students bought 10 packagesRolls.
each package contains 9 rolls.
some of the students bought 7 packages of juice boxes.
each package contains 10 juice boxes.
7 x 10 = 70.
10 + 10 + 10 + 10 + 10 + 10 + 10 = 70.
so the total number of juice boxes bought for a school picnic = 70.

Question 19.
Higher Order Thinking Greg bikes 9 miles and swims 4 miles each week. He multiplied 5 x 10 to find how many more miles he biked than swam in the last 10 weeks. Does that make sense? Why or why not?

Answer:
Assessment Practice

Question 20.
Kinsey arranges her buttons in 4 equal groups of 10. Mara arranges her buttons in 9 equal groups of 10. Seth arranges his buttons in 3 equal groups of 10. Select numbers to complete the equations that represent the button arrangements.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 90.7

Answer:
The missing numbers are 40, 9, and 10.

Explanation:
In the above-given question,
given that,
Kinsey arranges her buttons in 4 equal groups of 10.
Mara arranges her buttons in 9 equal groups of 10.
Seth arranges his buttons in 3 equal groups of 10.
4 x 10 = 40.
9 x 10 = 90.
3 x 10 = 30.
so the missing numbers are 40, 9, and 10.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-26

Question 21.
Mark arranges his cards in 2 equal rows of 10. Jeff arranges his cards in 7 equal rows of 10. Paul arranges his cards in 10 equal rows of 10. Select numbers to complete the equations that represent the card arrays.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 90.8

Answer:
The missing numbers are 10, 7, and 100.

Explanation:
In the above-given question,
given that,
Mark arranges his cards in 2 equal rows of 10.
Jeff arranges his cards in 7 equal rows of 10.
Paul arranges his cards in 10 equal rows of 10.
2 x 10 = 20.
7 x 10 = 70.
10 x 10 = 100.
so the missing numbers are 10, 7, and 100.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-27

Lesson 2.5 Multiplication Facts: 0, 1, 2, 5, 9, and 10

Activity

Solve & Share

A company sells boxes of colored pencils. Each box contains 5 pencils. How many pencils are in 5 boxes? 9 boxes? 10 boxes? Explain how you found your answers.

Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 91.1

Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 91.2
You can use appropriate tools to make an array to show the multiplication.

Answer:
The number of pencils in 5 boxes = 25.
the number of pencils in 9 boxes = 45.
the number of pencils in 10 boxes = 50.

Explanation:
In the above-given question,
given that,
each box contains 5 pencils.
1 box = 1 x 5.
5 boxes = 5 x 5 = 25.
9 boxes = 9 x 5 = 45.
10 boxes = 10 x 5 = 50.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-28

Look Back!
A different company sells boxes that have 9 colored pencils in each box. How many pencils are in 5 boxes? 9 boxes? 10 boxes?

Answer:
The number of pencils in 5 boxes = 45.
the number of pencils in 9 boxes = 81.
the number of pencils in 10 boxes = 90.

Explanation:
In the above-given question,
given that,
each box contains 9 pencils.
1 box = 1 x 9.
5 boxes = 5 x 9 = 45.
9 boxes = 9 x 9 = 81.
10 boxes = 10 x 9 = 90.

Visual Learning Bridge

Essential Question

How Do You Use Multiplication Facts to Solve Problems?

A.
Brendan has archery practice. The target shows the points he gets for hitting a section. How many points did Brendan get from his arrows that hit the black ring? How many points did he get from the red ring?
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 91.10

B.
8 arrows hit the black ring.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 91.11
The bar diagram shows 8 equal groups of 2. 8 × 2 = 16
Brendan got 16 points from the 8 arrows.

C. 4 arrows hit the red ring.
Envision Math Common Core Grade 3 Answers Topic 2 Multiplication Facts Use Patterns 91.12
Skip count and record your counts. 9, 18, 27, 36
4 × 9 = 36
Brendan got 36 points from the 4 arrows.

Convince Me!
Be Precise How many points did Brendan get from the arrows that hit the yellow ring? Explain how you know.

Answer:
The number of points that hit the yellow ring = 30.

Explanation:
In the above-given question,
given that,
3 arrows hit the yellow ring.
3 x 10 = 30.
skip count 3 times.
10 + 10 + 10 = 30.
so the number of points that hit the yellow ring = 30.

Guided Practice

Do You Understand?

Question 1.
To find 6 × 5, how does knowing 5 × 6 = 30 help you?

Answer:
5 x 6 is a commutative property.

Explanation:
In the above-given question,
given that,
6 x 5 = 5 x 6.
this is a commutative property.
so in finding 6 x 5, 5 x 6 = 30 helps us.
6 x 5 = 30.

Question 2.
How can you find 8 + 8 + 8 + 8 + 8 without adding?

Answer:
5 x 8 = 40.

Explanation:
In the above-given question,
given that,
8 + 8 + 8 + 8 + 8 = 48.
we can also find it in another way.
there are five groups of 8.
5 x 8 = 40.

Do You Know How?

In 3-9, find each product.

Question 3.
5 × 9 = ___

Answer:
The product is 45.

Explanation:
In the above-given question,
given that,
5 x 9 = 45.
here 5 and 9 are the factors.
45 is the product.

Question 4.
__ = 2 × 1

Answer:
The product is 2.

Explanation:
In the above-given question,
given that,
2 x 1 = 2.
here 1 and 2 are the factors.
2 is the product.

Question 5.
___ = 0 × 10

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
0 x 10 = 0.
here 0 and 10 are the factors.
0 is the product.

Question 6.
5 × 4 = ___

Answer:
The product is 20.

Explanation:
In the above-given question,
given that,
5 x 4 = 20.
here 5 and 4 are the factors.
20 is the product.

Question 7.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 92.1

Answer:
The product is 2.

Explanation:
In the above-given question,
given that,
1 x 2 = 2.
here 1 and 2 are the factors.
2 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-29

Question 8.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.1

Answer:
The product is 14.

Explanation:
In the above-given question,
given that,
2 x 7 = 14.
here 2 and 7 are the factors.
14 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-30

Question 9.
What is 4 × 9?

Answer:
The product is 36.

Explanation:
In the above-given question,
given that,
4 x 9 = 36.
here 4 and 9 are the factors.
36 is the product.

Independent Practice

In 10-26, find each product.

Question 10.
2 × 5 = ___

Answer:
The product is 10.

Explanation:
In the above-given question,
given that,
2 x 5 = 10.
here 2 and 5 are the factors.
10 is the product.

Question 11.
___ = 9 × 0

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
9 x 0 = 0.
here 0 and 9 are the factors.
0 is the product.

Question 12.
1 × 4 = ___

Answer:
The product is 4.

Explanation:
In the above-given question,
given that,
1 x 4 = 4.
here 1 and 4 are the factors.
4 is the product.

Question 13.
___ = 6 × 2

Answer:
The product is 12.

Explanation:
In the above-given question,
given that,
6 x 2 = 12.
here 6 and 2 are the factors.
12 is the product.

Question 14.
10 × 6 = __

Answer:
The product is 60.

Explanation:
In the above-given question,
given that,
10 x 6 = 60.
here 10 and 6 are the factors.
60 is the product.

Question 15.
___ = 7 × 1

Answer:
The product is 7.

Explanation:
In the above-given question,
given that,
7 x 1 = 7.
here 1 and 7 are the factors.
7 is the product.

Question 16.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 933.1

Answer:
The product is 20.

Explanation:
In the above-given question,
given that,
2 x 10 = 20.
here 2 and 10 are the factors.
20 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-31

Question 17.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.2

Answer:
The product is 2.

Explanation:
In the above-given question,
given that,
2 x 1 = 2.
here 2 and 1 are the factors.
2 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-32

Question 18.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.3

Answer:
The product is 81.

Explanation:
In the above-given question,
given that,
9 x 9 = 81.
here 9 and 9 are the factors.
81 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-33

Question 19.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.4

Answer:
The product is 14.

Explanation:
In the above-given question,
given that,
7 x 2 = 14.
here 7 and 2 are the factors.
14 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-34

Question 20.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.5

Answer:
The product is 27.

Explanation:
In the above-given question,
given that,
9 x 3 = 27.
here 9 and 3 are the factors.
27 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-35

Question 21.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.6

Answer:
The product is 0.

Explanation:
In the above-given question,
given that,
0 x 7 = 0.
here 0 and 7 are the factors.
0 is the product.

Question 22.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.7

Answer:
The product is 20.

Explanation:
In the above-given question,
given that,
5 x 4 = 20.
here 5 and 4 are the factors.
20 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-36

Question 23.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 93.8

Answer:
The product is 35.

Explanation:
In the above-given question,
given that,
5 x 7 = 35.
here 5 and 7 are the factors.
35 is the product.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-37

Question 24.
What is 1 × 1?

Answer:
The product is 1.

Explanation:
In the above-given question,
given that,
1 x 1 = 1.
here 1 and 1 are the factors.
1 is the product.

Question 25.
What is 10 × 10?

Answer:
The product is 100.

Explanation:
In the above-given question,
given that,
10 x 10 = 100.
here 10 and 10 are the factors.
100 is the product.

Question 26.
What is 3 × 9?

Answer:
The product is 27.

Explanation:
In the above-given question,
given that,
3 x 9 = 27.
here 3 and 9 are the factors.
27 is the product.

Problem Solving

Question 27.
Critique Reasoning Abdi says that 9 × 6 is less than 10 × 4 because 9 is less than 10. Do you agree with Abdi’s reasoning? Explain why or why not.

Answer:
No, I do not agree with that.

Explanation:
In the above-given question,
given that,
Abdi says that 9 x 6 is less than 10 x 4 because 9 is less than 10.
9 x 6 = 54.
10 x 4 = 40.
54 is greater than 40.
so i do not agree.

Question 28.
Victoria has 5 pairs of shoes. What equation could Victoria write to find out how many shoes she has?

Answer:
The number of shoes she has = 10.

Explanation:
In the above-given question,
given that,
victoria has 5 pairs of shoes.
5 x 2 = 10.
5 + 5 = 10.
so the number of shoes she has = 10.

Question 29.
Show 7:50 on the clock.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 94.1

Answer:
The minute hand on the 10.
the hour hand on the 7.

Explanation:
In the above-given question,
given that,
the time is 7:50.
the minute hand on the 10.
the hour hand on the 7.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-38

Question 30.
Robb has 35 red counters and 39 yellow counters. He gives his sister 18 red counters. How many counters does Robb have left?

Answer:
The number of counters Robb has = 56.

Explanation:
In the above-given question,
given that,
Robb has 35 red counters and 39 yellow counters.
He gives his sister 18 red counters.
35 – 18 = 17.
17 + 39 = 56.
so the number of counters Robb have = 56

Question 31.
Kim makes an array with 4 rows and 9 columns. Rashida makes an array with 9 rows and 4 columns. Whose array has more items? Explain.

Answer:
Kim and Rashida have an equal number of items.

Explanation:
In the above-given question,
given that,
Kim makes an array with 4 rows and 9 columns.
Rashida makes an array with 9 rows and 4 columns.
4 x 9 = 36.
9 x 4 = 36.
so both have an equal number of items.

Question 32.
Higher Order Thinking Brendan shot 3 arrows in the 10-point section, 4 arrows in the 9-point section, 9 arrows in the 5-point section, 8 arrows in the 2-point section, and 7 arrows in the 1-point section. What is the total number of points Brendan scored for all his arrows?

Answer:
The total number of points Brendan scored for all his arrows = 25.

Explanation:
In the above-given question,
given that,
Brendan shot 3 arrows in the 10-point section.
4 arrows in the 9-point section.
9 arrows in the 5-point section.
8 arrows in the 2-point section.
7 arrows in the 1-point section.
10 + 9 + 5 + 2 + 1 = 27.
so the total number of points Brendan scored for all his arrows = 25.

Assessment Practice

Question 33.
Craig visits a railroad museum and takes photos of engines. He arranges his photos into an array with 5 equal rows of 9 photos. How many photos are in Craig’s array?
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 95.1
Think about the different ways you know to find and represent multiplication facts.
A. 5
B. 9
C. 45
D. 59

Answer:
The number of points is in Craig’s array = 45.

Explanation:
In the above-given question,
given that,
Craig visits a railroad museum and takes photos of engines.
He arranges his photos into an array with 5 equal rows of 9 photos.
5 x 9 = 45.
9 + 9 + 9 + 9 + 9 = 45.
so the number of points is Craig’s array = 45.

Lesson 2.6 Model with Math

Problem Solving

Activity

Solve & Share

At the pet store, Sam bought a hamster that cost $10. He also bought 5 mice at $4 each. How much did Sam spend in all? Write to explain the math you used to solve this problem.

Answer:
The amount did Sam spend in all = $30.

Explanation:
In the above-given question,
given that,
At the pet store, Sam bought a hamster that cost $10.
He also bought 5 mice at $4 each.
5 x 4 = 20.
10 + 20 = 30.
so the amount did Sam spend in all = $30.

Thinking Habits
Be a good thinker! These questions can help you.
• How can I use math I know to help solve this problem?
• How can I use pictures, objects, or an equation to represent the problem?
• How can I use numbers, words, and symbols to solve the problem?
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 95.11

Look Back!
Model with Math How would your answer above change if Sam only bought 4 mice?

Answer:
The answer is 16.

Explanation:
In the above-given question,
given that,
He also bought 4 mice at $4 each.
4 x 4 = 16.
so the amount did Sam spend in all = $16.

Visual Learning Bridge

Essential Question
How Can You Model with Math?

A.
Keisha bought 2 yards of felt to make some puppets. Tanya bought 6 yards of felt. Each yard of felt costs the same amount. How much did the girls spend on felt in all?
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 95.2
What math do I need to use to solve this problem?
I need to show what I know and then choose the needed operations.

B.
How can I model with math?
I can

  • use the math I know to solve the problem.
  • find and answer any hidden questions.
  • use diagrams and equations to represent and solve this problem.

C.
Here’s my thinking…
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.1
I will use bar diagrams and equations.
The hidden question is: How many yards of felt did the girls buy?
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.2
2 + 6 = ?
2 + 6 = 8. The girls bought 8 yards of felt.
So, I need to find the cost of 8 yards at $2 per yard.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.3
8 × $2 = ?
8 × $2 = $16. The girls spent $16.

Convince Me!
Model with Math Use these number lines to show another way to represent the problem above.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.4

Answer:
2 + 6 = 8.
8 x 2 = 16.

Explanation:
In the above-given question,
given that,
The girls bought 8 yards of felt.
So, I need to find the cost of 8 yards at $2 per yard.
8 × $2 = $16. The girls spent $16.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-39

Guided Practice

Model with Math
A pack of gum contains 5 pieces. Phil had 7 packs of gum before he lost 2 pieces. How many pieces of gum does Phil have now?

Model with math.
You can represent and solve each step in a two-step problem.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.44

Answer:
The number of pieces of gum does Phil have now = 35 pieces.

Explanation:
In the above-given question,
given that,
A pack of gum contains 5 pieces.
Phil had 7 packs of gum before he lost 2 pieces.
5 + 2 = 7.
7 x 5 = 35.
so the number of pieces of gum does phil have now = 35.

Question 1.
What is the hidden question you need to answer before you can solve the problem?

Answer:
The hidden answer is he had 7 pieces of gum.

Explanation:
In the above-given question,
given that,
A pack of gum contains 5 pieces.
Phil had 7 packs of gum before he lost 2 pieces.
5 + 2 = 7.
7 x 5 = 35.
so the number of pieces of gum does phil have now = 35.

Question 2.
Solve the problem. Complete the bar diagrams. Show the equations you used.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.5

Answer:
7 x 5 = 35.
5 + 7 = 12.

Explanation:
In the above-given question,
given that,
A pack of gum contains 5 pieces.
Phil had 7 packs of gum before he lost 2 pieces.
5 + 2 = 7.
7 x 5 = 35.
so the number of pieces of gum does phil have now = 35.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-40

Independent Practice

Model with Math

Jen bought 4 tickets. Amber bought 5 tickets. The tickets cost $2 each. How much did the girls spend on tickets in all?

Question 3.
What is the hidden question you need to answer before you can solve the problem?

Answer:
The girls spend on tickets in all = 18 dollars.

Explanation:
In the above-given question,
given that,
Jen bought 4 tickets.
Amer bought 5 tickets.
The tickets cost $2 each.
5 + 4 = 9.
9 x 2 = 18.
so the girls spend on tickets in all = $18.

Question 4.
Solve the problem. Complete the bar diagrams. Show the equations you used.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.6

Answer:
The total money spends in all = $18.

Explanation:
In the above-given question,
given that,
Jen bought 4 tickets.
Amber bought 5 tickets.
The tickets cost $2 each.
5 + 4 = 9.
9 x 2 = 18.
so the girls spend on tickets in all = $18.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-41

Question 5.
How would your equations change if Amber bought only 3 tickets? Explain.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.7

Answer:
The girls spend on tickets in all = 14 dollars.

Explanation:
In the above-given question,
given that,
Jen bought 4 tickets.
Amber bought 3 tickets.
The tickets cost $2 each.
3 + 4 = 7.
7 x 2 = 14.
so the girls spend on tickets in all = $14.

Problem Solving

Performance Task

Coffee Shop
David and Jon are placing coffee orders for their friends. David orders 10 large cups of coffee. Jon orders 4 fewer large cups than David. Jon pays for his orders with a $50 bill. Jon wants to know how much he spent on coffee.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.8

Question 6.
Make Sense and Persevere What is a good plan to find the amount Jon spent on coffee?

Answer:
The amount Jon spent on Coffee = 16 dollars.

Explanation:
In the above-given question,
given that,
David and Jon are placing coffee orders for their friends.
David orders 10 large cups of coffee.
Jon orders 4 fewer large cups than David.
Jon pays for his orders with a $50 bill.
4 x 4 = 16.
4 + 4 + 4 + 4 = 16.
so the amount Jon spent on Coffee = 16 dollars.

Question 7.
Model with Math Find how much Jon spent on coffee. Complete the bar diagrams. Show the equations you used.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 960

Answer:
The amount Jon spent on Coffee = 16 dollars.

Explanation:
In the above-given question,
given that,
David and Jon are placing coffee orders for their friends.
David orders 10 large cups of coffee.
Jon orders 4 fewer large cups than David.
Jon pays for his orders with a $50 bill.
4 x 4 = 16.
4 + 4 + 4 + 4 = 16.
so the amount Jon spent on Coffee = 16 dollars.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-42

Question 8.
Critique Reasoning Jamie says the equation 0 × $2 = $0 shows the amount Jon spent on small cups of coffee. Is he correct? Explain.

Answer:
Yes, Jamie was correct.

Explanation:
In the above-given question,
given that,
Jamie says the equation 0 x $2 = $0.
0 x 2 = 0.
so Jamie was correct.

Question 9.
Reasoning Would David have enough money if he paid for his order with a $20 bill? Explain.

Model with math. Think about the math you know to solve the problem.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 96.9

Topic 2 Fluency Review

Activity

Point & Tally

Find a partner. Get paper and a pencil. Each partner chooses a different color: light blue or dark blue.
Partner 1 and Partner 2 each point to a black number at the same time. Both partners add those numbers.
If the answer is on your color, you get a tally mark. Work until one partner has seven tally marks.

Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 98.1.

Topic 2 Vocabulary Review

Glossary

Understand Vocabulary
Circle all correct responses.

Word List
• bar diagram
• factor
• Identity (One) Property of Multiplication
• multiplication
• multiples
• product
• Zero Property of Multiplication

Question 1.
Circle each number that is a product.
4 × 6 = 24 7 × 3 = 21 8 ÷ 4 = 2

Answer:
4 x 6 = 24 and 7 x 3 = 21.

Explanation:
In the above-given question,
given that,
the product is 4 x 6.
4 x 6 = 24.
7 x 3 = 21.

Question 2.
Circle each example of the Identity Property.
2 × 2 = 4 5 × 0 = 0 1 × 6 = 6

Answer:
The Identity property is 1 x 6 = 6.

Explanation:
In the above-given question,
given that,
Identity property is the number multiplied by 1, we will get the same number.
1 x 6 = 6.
6 x 1 = 6.
so the identity property is 1 x 6 = 6.

Question 3.
Circle each example of the Zero Property.
1 × 0 = 0 0 × 9 = 0 2 × 5 = 10

Answer:
1 x 0 = 0 and 0 x 9 = 0.

Explanation:
In the above-given question,
given that,
zero property is anything we multiply by 0 we will get 0.
1 x 0 = 0.
0 x 9 = 0.

Question 4.
Circle each equation that shows multiplication.
5 + 6 = 11 4 × 4 = 16 17 – 12 = 5 16 ÷ 2 = 8

Answer:
4 x 4 = 16.

Explanation:
In the above-given question,
given that,
the equations are 5 + 6 = 11.
4 x 4 = 16 is an multiplication equation.

Question 5.
Skip count by 9s. Circle each number that is a multiple of 9.
16 9 28 27 19 36 18 39

Answer:
The multiple of 9 is 9, 18, 27, 36.

Explanation:
In the above-given question,
given that,
skip count by 9’s.
multiple of 9 are:
9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.

Write T for true or F for false.

______ Question 6.
Skip count by 4s. The number 14 is a multiple of 4.

Answer:
False.

Explanation:
In the above-given question,
given that,
skip count by 4s.
4 x 1 = 4.
4 x 2 = 8.
4 x 3 = 12.
so 14 is not a multiple of 4.

_______ Question 7.
The Identity Property says that any number times 1 equals the number itself.

Answer:
True.

Explanation:
In the above-given question,
given that,
identity property:
any number that multiplies by 1 we will get the same number.
for example:
5 x 1 = 5.
1 x 5 = 5.
so the given question is true.

______ Question 8.
A bar diagram can be used to show 3 × 6.

Answer:
3 x 6 = 18.

Explanation:
In the above-given question,
given that,
3 x 6 = 18.
bar diagram is not used to show 3 x 6.
3 x 6 = 18.

Use Vocabulary in Writing

Question 9.
Explain how you can find the product 4 × 2 and the product 8 × 2. Use at least 3 terms from the Word List in your explanation.

Answer:
4 x 2 = 8.
8 x 2 = 16.

Explanation:
In the above-given question,
given that,
4 x 2 = 8.
8 x 2 = 16.
here we use the commutative property.

Topic 2 Reteaching

Set A
pages 41-44

Find 6 × 2.
Use skip counting. Draw 6 curved arrows on a number line. Each arrow should be 2 units wide.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.1
Find 6 × 5.
Use a pattern. Count by 5s. The 6th number in the pattern is the product.
5, 10, 15, 20, 25, 30 6 × 5 = 30

Remember that multiples of 2 end in 0, 2, 4, 6, or 8. Multiples of 5 end in 0 or 5.

Question 1.
2 × 3 = ___

Answer:
2 x 3 = 6.

Explanation:
In the above-given question,
given that,
multiples of 2 end in 0, 2, 4, 6, and 8.
3 + 3 = 6.
2 x 1 = 2.
2 x 2 = 4.
2 x 3 = 6.

Question 2.
5 × 3 = ___

Answer:
5 x 3 = 15.

Explanation:
In the above-given question,
given that,
multiples of 5 end in 0, 5, 10, and 15.
5 x 1 = 5.
5 x 2 = 10.
5 x 3 = 15.
3 + 3 + 3 + 3 + 3 = 15.

Question 3.
5 × 5 = ___

Answer:
5 x 5 = 25.

Explanation:
In the above-given question,
given that,
multiples of 5 end in 0, 5, 10, and 15.
5 x 1 = 5.
5 x 2 = 10.
5 x 3 = 15.
5 x 4 = 20.
5 x 5 = 25.
5 + 5 + 5 + 5 + 5 = 25.

Question 4.
2 × 6 = ___

Answer:
2 x 6 = 12.

Explanation:
In the above-given question,
given that,
multiples of 2 end in 0, 2, 4, 6, and 8.
2 + 2 + 2 + 2 + 2 + 2 = 12.
2 x 1 = 2.
2 x 2 = 4.
2 x 3 = 6.
2 x 4 = 8.
2 x 5 = 10.
2 x 6 = 12.

Question 5.
8 × 2 = ___

Answer:
8 x 2 = 16.

Explanation:
In the above-given question,
given that,
multiples of 2 end in 0, 2, 4, 6, and 8.
2 + 2 + 2 + 2 + 2 + 2 + 2 + 2 = 16.
8 x 1 = 8.
8 x 2 = 16.

Question 6.
7 × 5 = __

Answer:
7 x 5 = 35.

Explanation:
In the above-given question,
given that,
multiples of 5 end in 0, 5, 10, and 15.
5 + 5 + 5 + 5 + 5 = 35.
7 x 1 = 7.
7 x 2 = 14.
7 x 3 = 21.
7 x 4 = 28.
7 x 5 = 35.

Question 7.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.3

Answer:
2 x 2 = 4.

Explanation:
In the above-given question,
given that,
multiples of 2 end in 0, 2, 4, 6, and 8.
2 + 2 = 4.
2 x 1 = 2.
2 x 2 = 4.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-43

Question 8.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.4

Answer:
7 x 2 = 14.

Explanation:
In the above-given question,
given that,
multiples of 2 end in 0, 2, 4, 6, and 8.
2 + 2 + 2 + 2 + 2 + 2 + 2  = 14.
7 x 1 = 7.
7 x 2 = 14.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-44

Question 9.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.5

Answer:
8 x 5 = 40.

Explanation:
In the above-given question,
given that,
multiples of 5 end in 0, 5, 10, and 15.
5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 = 35.
8 x 1 = 8.
8 x 2 = 16.
8 x 3 = 24.
8 x 4 = 32.
8 x 5 = 40.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-45

Question 10.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.6

Answer:
9 x 5 = 45.

Explanation:
In the above-given question,
given that,
multiples of 5 end in 0, 5, 10, and 15.
5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 = 45.
9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.
9 x 5 = 45.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-46

Set B
pages 45-48

Find 9 × 4.
List 9s facts.
9 × 1 = 9
9 × 2 = 18
9 × 3 = 27
9 × 4 = 36

Remember that there are patterns in the multiples of 9.

Question 1.
9 × 5 = ___

Answer:
9 x 5 = 45.

Explanation:
In the above-given question,
given that,
the multiples of 9 are 9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.
9 x 5 = 45.
9 and 5 are the factors.
45 is the product.

Question 2.
9 × 7 = ___

Answer:
9 x 7 = 63.

Explanation:
In the above-given question,
given that,
the multiples of 9 are:
9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.
9 x 5 = 45.
9 x 6 = 54.
9 x 7 = 63.
9 and 7 are the factors.
63 is the product.

Question 3.
6 × 9 = ___

Answer:
6 x 9 = 54.

Explanation:
In the above-given question,
given that,
the multiples of 9 are:
9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.
9 x 5 = 45.
9 x 6 = 54.
9 and 6 are the factors.
54 is the product.

Question 4.
8 × 9 = ___

Answer:
8 x 9 = 72.

Explanation:
In the above-given question,
given that,
the multiples of 9 are:
9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.
9 x 5 = 45.
9 x 6 = 54.
9 x 7 = 63.
9 x 8 = 72.
9 and 8 are the factors.
72 is the product.

Question 5.
9 × 9 = ___

Answer:
9 x 9 = 81.

Explanation:
In the above-given question,
given that,
the multiples of 9 are:
9 x 1 = 9.
9 x 2 = 18.
9 x 3 = 27.
9 x 4 = 36.
9 x 5 = 45.
9 x 6 = 54.
9 x 7 = 63.
9 x 8 = 72.
9 x 9 = 81.
9 and 9 are the factors.
81 is the product.

Question 6.
9 × 0 = ___

Answer:
9 x 0 = 0.

Explanation:
In the above-given question,
given that,
the multiples of 9 are:
9 x 0 = 0.
9 is the factor.
0 is the product.

Set C
pages 49-52
Find 0 × 7.

Zero Property of Multiplication: When you multiply a number by 0, the product is 0.
0 × 7 = 0
Find 1 × 7.

Remember that the product of O and any other number is 0. When you multiply a number by 1, the product is that same number.

Question 1.
0 × 4 = ___

Answer:
0 x 4 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 4 = 0.
4 x 0 = 0.

Question 2.
1 × 9 = ___

Answer:
1 x 9 = 9.

Explanation:
In the above-given question,
given that,
when we multiply a number by 1, we will get the same number.
1 x 9 = 9.
9 x 1 = 9.

Question 3.
0 × 9 = ___

Answer:
0 x 9 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 9 = 0.
9 x 0 = 0.

Question 4.
1 × 6 = ___

Answer:
1 x 6 = 6.

Explanation:
In the above-given question,
given that,
when we multiply a number by 1, we will get the same number.
1 x 6 = 6.
6 x 1 = 6.

Question 5.
10 × 0 = ___

Answer:
10 x 0 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 10 = 0.
10 x 0 = 0.

Question 6.
9 × 0 = ___

Answer:
9 x 0 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 9 = 0.
9 x 0 = 0.

Question 7.
3 × 1 = ___

Answer:
1 x 3 = 3.

Explanation:
In the above-given question,
given that,
when we multiply a number by 1, we will get the same number.
1 x 3 = 3.
3 x 1 = 3.

Question 8.
8 × 1 = ___

Answer:
1 x 8 = 8.

Explanation:
In the above-given question,
given that,
when we multiply a number by 1, we will get the same number.
1 x 8 = 8.
8 x 1 = 8.

Question 9.
0 × 2 = ___

Answer:
0 x 2 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 2 = 0.
2 x 0 = 0.

Question 10.
1 × 0 = ___

Answer:
0 x 1 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 1 = 0.
1 x 0 = 0.

Set D
pages 53-56
Find 6 × 10.
You can use patterns to find multiples of 10.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.20
6 × 10 is 6 groups of 10.
6 × 10 = 60

Remember that you can use place value or number lines to find multiples of ten.

Question 1.
10 × 7 = ___

Answer:
10 x 7 = 70.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 7 is 7 groups of 10.
7 x 10 = 70.

Question 2.
10 × 10 = ___

Answer:
10 x 10 = 100.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 10 is 10 groups of 10.
10 x 10 = 100.

Question 3.
3 × 10 = ___

Answer:
10 x 3 = 30.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 3 is 3 groups of 10.
3 x 10 = 30.

Question 4.
9 × 10 = ___

Answer:
10 x 9 = 90.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 9 is 9 groups of 10.
9 x 10 = 90.

Question 5.
10 × 0 = __

Answer:
10 x 0 = 0.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 0 is 0 groups of 10.
0 x 10 = 0.

Question 6.
1 × 10 = ___

Answer:
10 x 1 = 10.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 1 is 1 group of 10.
1 x 10 = 10.

Set E
pages 57-60
Find 5 × 10.
There are many patterns and properties you can use to multiply.
Use skip counting with 5s facts:
5, 10, 15, 20, 25, 30, 35, 40, 45, 50
Use a place-value pattern for 10s facts: 10 times greater than 5 is 50.
The product is the same. 5 × 10 = 50

Remember that you can use the Commutative Property of Multiplication to multiply 2 factors in any order.

Question 1.
5 × 9 = ___

Answer:
5 x 9 = 45.

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 9.
5 x 9 is 5 groups of 9.
5 x 1 = 5.
5 x 2 = 10.
5 x 3 = 15.
5 x 4 = 20.
5 x 5 = 25.
5 x 6 = 30.
5 x 7 = 35.
5 x 8 = 40.
5 x 9 = 45.

Question 2.
0 × 6 = ___

Answer:
0 x 6 = 0.

Explanation:
In the above-given question,
given that,
when we multiply by 0 we will get the product 0.
0 x 6 = 0.
6 x 0 = 0.

Question 3.
10 × 3 = ___

Answer:
10 x 3 = 30

Explanation:
In the above-given question,
given that,
we can use patterns to find multiples of 10.
10 x 3 is 3 groups of 10.
3 x 10 = 30.

.Question 4.
8 × 1 = ___

Answer:
8 x 1 = 8.

Explanation:
In the above-given question,
given that,
when we multiply a number by 1, we will get the same number.
1 x 8 = 8.
8 x 1 = 8.

Question 5.
7 × 2 = __

Answer:
7 x 2 = 14.

Explanation:
In the above-given question,
given that,
multiples of 2 end in 0, 2, 4, 6, and 8.
2 + 2 + 2 + 2 + 2 + 2 + 2 = 14.
7 x 1 = 7.
7 x 2 = 14.

Question 6.
9 × 6 = __

Answer:

Question 7.
2 × 5 = __

Answer:
2 x 5 = 10.
multiples of 2 end in 0, 2, 4, 6, and 8.
2 + 2 + 2 + 2 + 2 = 10.
2 x 1 = 2.
2 x 2 = 4.
2 x 3 = 6.
2 x 4 = 8.
2 x 5 = 10.

Question 8.
4 × 5 = ___

Answer:
4 x 5 = 20.

Explanation:
In the above-given question,
given that,
multiples of 5 end in 0, 5, 10, and 15.
5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 = 45.
5 x 1 = 5.
5 x 2 = 10.
5 x 3 = 15.
5 x 4 = 20.
Set F
pages 61-64
Think about these questions to help you model with math.

Thinking Habits
• How can I use math I know to help solve the problem?
• How can I use pictures, objects, or an equation to represent the problem?
• How can I use numbers, words, and symbols to solve the problem?
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.21

Remember that representations can help you apply math that you know.
Umar has 5 dimes in his left pocket. He has 3 dimes in his right pocket. A dime is worth 10 cents. How much money does Umar have?

Question 1.
Draw a bar diagram to help answer the hidden question.

Answer:
The money Umar has = 80.

Explanation:
In the above-given question,
given that,
Umar has 5 dimes in his left pocket.
he has 3 dimes in his right pocket.
a dime is worth 10 cents.
5 + 3 = 8.
8 x 10 = 80.
so the money Umar has = 80.

Question 2.
Draw a bar diagram to help answer the main question.

Answer:
The money Umar has = 80.

Explanation:
In the above-given question,
given that,
Umar has 5 dimes in his left pocket.
he has 3 dimes in his right pocket.
a dime is worth 10 cents.
5 + 3 = 8.
8 x 10 = 80.
so the money Umar has = 80.

Topic 2 Assessment Practice

Question 1.
A building has 9 rows of mailboxes. There are 6 mailboxes in each row. Write and solve an equation to find the total number of mailboxes.

Answer:
The total number of mailboxes = 54.

Explanation:
In the above-given question,
given that,
A building has 9 rows of mailboxes.
there are 6 mailboxes in each row.
9 x 6 = 54.
6 + 6 + 6 + 6 + 6 + 6 + 6 + 6 + 6 = 54.
so the total number of mailboxes = 54.

Question 2.
Tickets to a juggling show cost $2 for each child. Three children go to see the show. What is the total cost of their tickets?
A. Draw a bar diagram and write an equation to solve the problem.
B. What is the total cost of the children’s tickets?

Answer:
The total cost of their children = $6.

Explanation:
In the above-given question,
given that,
Tickets to a juggling show cost $2 for each child.
Three children go to see the show.
3 x 2 = 6.
2 + 2 + 2 = 6.
so the total cost of their children = $6.

Question 3.
Cindy got 9 questions correct on an assignment. Each question is worth 4 points. She wrote the expression 9 × 4 to represent how many points she earned in all. Which expression is equal to 9 × 4?
A. 9 × 5
B. 5 × 4
C 4 × 9
D. 4 × 6

Answer:
Option C is correct.

Explanation:
In the above-given question,
given that,
Cindy got 9 questions correct on an assignment.
Each question is worth 4 points.
9 x 4 = 36.
4 x 9 = 36.
so option C is correct.

Question 4.
Harry told Arthur he baked 35 cookies on a rectangular pan. Which sentence could Arthur use to describe how the cookies were baked?
A. Harry baked 7 rows of 6 cookies.
B. Harry baked 5 rows of 5 cookies.
C. Harry baked 7 rows of 7 cookies.
D. Harry baked 7 rows of 5 cookies.

Answer:
Option D is correct.

Explanation:
In the above-given question,
given that,
Harry told Arthur he baked 35 cookies on a rectangular pan.
7 rows and 5 columns.
7 x 5 = 35.
so option D is correct.

Question 5.
Alex has 8 dimes in his pocket. A dime is worth 10 cents. Write an expression that represents how many cents Alex has in his pocket. How much money does he have?

Answer:
The money does Alex have =

Explanation:
In the above-given question,
given that,
Alex has 8 dimes in his pocket. A dime is worth 10 cents.
8 x 10 = 80.
10 + 10 + 10 + 10 + 10 + 10 + 10 + 10 = 80.
8 x 1 = 8.
8 x 2 = 16.
8 x 3 = 24.
8 x 4 = 32.
8 x 5 = 40.
8 x 6 = 48.
8 x 7 = 56.
8 x 8 = 64.
8 x 9 = 72.
8 x 10 = 80.

Question 6.
Which number completes the equation? Select all that apply.
___ × 0 = 0
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 15.0 0
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 15.0 9
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 15.0 2
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 15.0 10
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 15.0 5

Answer:
0 x 0 = 0.
9 x 0 = 0.
2 x 0 = 0.
10 x 0 = 0.
5 x 0 = 0.

Explanation:
In the above-given question,
given that,
anything if we multiply by 0 the product is 0.
0 x 0 = 0.
9 x 0 = 0.
2 x 0 = 0.
10 x 0 = 0.
5 x 0 = 0.

Question 7.
Ben says that when any number between 1 and 9 is multiplied by 5, the product always has a 0 or 5 in the ones place. Is this reasonable? Explain.

Answer:
Yes, Ben was correct.

Explanation:
In the above-given question,
given that,
Ben says that when any number between 1 and 9 is multiplied by 5.
the product always has a 0 or 5 in the ones place.
for example:
1 x 5 = 5.
2 x 5 = 10.
3 x 5 = 15.
4 x 5 = 20.
5 x 5 = 25.
6 x 5 = 30.
7 x 5 = 35.
8 x 5 = 40.
9 x 5 = 45.
10 x 5 = 50.

Question 8.
Gabe has 5 birdcages. He keeps 5 birds in each cage. How many birds does Gabe have? Use a bar diagram to represent the problem.

Answer:
The number of birds does Gabe have = 25 birds.

Explanation:
In the above-given question,
given that,
Gabe has 5 birdcages.
5 birds in each cage.
5 x 5 = 25.
5 + 5 + 5 + 5 + 5 = 25.
so the number of birds does Gabe have = 25.

Question 9.
A set of blocks has 4 different colors that make a pattern. The pattern repeats 10 times. Write and solve an equation to find the number of blocks.

Answer:
The number of blocks = 40.

Explanation:
In the above-given question,
given that,
A set of blocks has 4 different colors that make a pattern.
The pattern repeats 10 times.
10 x 4 = 40.
10 + 10 + 10 + 10 = 40.
so the number of blocks = 40.

Question 10.
Zach arranges his quarters into 6 rows and 5 columns. David arranges his quarters into 5 rows and 6 columns. Who has more quarters? Explain.

Answer:
Zach and David have an equal number of quarters.

Explanation:
In the above-given question,
given that,
Zach arranges his quarters into 6 rows and 5 columns.
6 x 5 = 30.
David arranges his quarters into 5 rows and 6 columns.
5 x 6 = 30.
so Zach and David have an equal number of quarters.

Question 11.
Use the expression 10 ×? where? represents a factor between 1 and 9. What is true about the digit in the ones place of each product? Explain.

Answer:
10 x 2 = 20.
10 x 3 = 30.
10 x 4 = 40.
10 x 5 = 50.
10 x 6 = 60.
10 x 7 = 70.
10 x 8 = 80.

Explanation:
In the above-given question,
given that,
10 x 2 = 20.
10 x 3 = 30.
10 x 4 = 40.
10 x 5 = 50.
10 x 6 = 60.
10 x 7 = 70.
10 x 8 = 80.

Question 12.
Dawn has 2 bananas. She cuts each banana into 8 slices. Write and solve an equation to find the number of banana slices that Dawn has.

Answer:
The number of banana slices that Dawn has = 16.

Explanation:
In the above-given question,
given that,
Dawn has 2 bananas.
she cuts each banana into 8 slices.
2 x 8 = 16.
8 + 8 = 16.
so the number of banana slices that Dawn has = 16.

Question 13.
Isabella has $45 to spend on shirts. All shirts in the store are on sale for $5 each. How many shirts can Isabella buy? Explain how you found your answer.

Answer:
The number of Isabella buys = $9.

Explanation:
In the above-given question,
given that,
Isabella has $45 to spend on shirts.
All shirts in the store are on sale for $5 each.
45 / 5 = 9.
5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 = 45.
so the number of Isabella buys = $9.

Topic 2 Performance Task

Selling Cards
A soccer team is selling boxes of cards to raise money. There are boxes of small, medium, and large cards. The team earns a different amount for each card type.
Boxes Sold

  • On Monday, Will sold 4 boxes of large cards.
  • On Wednesday, Mia sold 6 boxes of small cards and 3 boxes of large cards.

Use the Selling Boxes of Cards table and Boxes Sold list to answer Exercises 1 and 2.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.31

Question 1.
How much money did Will earn? Write a multiplication equation to solve.

Answer:
The money will earn = 41.

Explanation:
In the above-given question,
given that,
On Wednesday, Mia sold 6 boxes of small cards and 3 boxes of large cards.
6 x 1 = 6.
3 x 5 = 15.
15 + 6 = 21.
On Monday, Will sold 4 boxes of large cards.
4 x 5 = 20.
21 + 20 = 41.
so the money will earn = 41.

Question 2.
Complete the chart to find the amount that Mia earned for each card type.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.32
Use the Selling Boxes of Cards table to answer Exercise 3.

Answer:
The amount that Mia earned for each type = 45.

Explanation:
In the above-given question,
given that,
small = 3 x 5 = 15.
medium = 4 x 5 = 20.
large = 2 x 5 = 10.
15 + 20 + 10 = 45.
so the amount that Mia earned for each type = 45.
Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-2- Multiplication Facts- Use Patterns-47

Question 3.
For 7 days, Logan sold a box of medium cards every day. How much did Logan earn? Create a representation for the problem.

Answer:
The logan earn = 140.

Explanation:
In the above-given question,
given that,
for 7 days, Logan sold a box of medium cards every day.
20 x 7 = 140.
20 + 20 + 20 + 20 + 20 + 20 + 20 = 140.
so the logan earned 140.

Boxes Bought

  • Mrs. Carlson buys 1 box of medium cards.
  • Mr. Choi buys 6 boxes of small cards.
  • Mrs. Willis buys 7 boxes of medium cards and 9 boxes of large cards.

Use the Cards in Each Box table and Boxes Bought list to answer Exercises 4-6.

Question 4.
Part A
How many cards does Mr. Choi buy?
Part B
What is another way that Mr. Choi can buy the same number of cards?

Answer:
The number of cards Mr. Choi buys = 192.

Explanation:
In the above-given question,
given that,
Mrs. Carlson buys 1 box of medium cards.
Mr. Choi buys 6 boxes of small cards.
Mrs. Willis buys 7 boxes of medium cards and 9 boxes of large cards.
1 x 9 = 9.
6 x 5 = 30.
7 x 9 = 63.
9 x 10 = 90.
9 + 30 + 90 + 63 = 192.
so the number of cards Mr. Choi buy = 192.

Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.33

Question 5.
Is there another way that Mrs. Carlson can buy the same number of cards? Explain.

Answer:
Yes, there is another way to buy the same number of cards.

Explanation:
In the above-given question,
given that,
carlson buys box of small cards = 5.
box of medium cards = 9.
box of large cards = 10.
5 + 9 + 10 = 24,

Question 6.
Complete the chart to find the number of cards Mrs. Willis buys of each card type.
Envision Math Common Core 3rd Grade Answer Key Topic 2 Multiplication Facts Use Patterns 99.35

Answer:
The total number of cards = 24.

Explanation:
In the above-given question,
given that,
the small number of boxes bought = 2.
the number of cards in a box = 3.
2 x 3 = 6.
the medium number of boxes bought = 2.
the number of cards in a box = 4.
2 x 4 = 8.
the large number of boxes bought = 2.
the number of cards in a box = 5.
2 x 5 = 10.
6 + 8 + 10 = 24.
so the total number of cards = 24.

Envision Math Common Core Grade 3 Answer Key

Envision Math Common Core Grade 3 Answer Key | Envision Math Common Core 3rd Grade Answers

enVision Math Grade 3 Answer Key provided here makes it easy for you to learn the Chapters within quite easily. Students of 3rd Grade can revise the entire Envision Math Common Core Grade 3 Syllabus smartly using the Volumewise Grade 3 Common Core enVision Math Answer Key.

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Envision Math Common Core Grade 3 Answers | Envision Math Common Core 3rd Grade Textbook Answer Key

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Envision Math Common Core Grade 3 Volume 1 Answer Key | Envision Math Common Core 3rd Grade Volume 1 Answers

Envision Math Common Core 3rd Grade Volume 3 Answer Key | Envision Math Common Core Grade 3 Volume 3 Answers

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Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data

enVision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data

Go through the enVision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data regularly and improve your accuracy in solving questions.

enVision Math Common Core 8th Grade Answers Key Topic 4 Investigate Bivariate Data

3-ACT MATH

Reach Out

Reach for the skies! Who in your class can reach the highest? That height depends on how tall each person is and the lengths of their arms.
Now stick your arms out to your sides. Sometimes this horizontal distance is called your wingspan. The wandering albatross can have a wingspan of up to 12 feet. How does your wingspan compare? Think about this during the 3-Act Mathematical Modeling lesson.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 1

enVision STEM Project

Did You Know?
A fishery biologist collects data on fish, such as the size and health of the fish population in a particular body of water.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 2
Largemouth bass and smallmouth bass are the most popular game fish in North America.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 4
Biologists often use tagging studies to estimate fish population, as well as to estimate catch and harvest rates.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 3
The average lifespan of bass is about 16 years, but some have lived more than 20 years.

Research suggests that bass can see red better than any other color on the spectrum.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 5

Your Task: How Many Fish?

Suppose a fishery biologist takes 500 basses from a lake, tags them, and then releases them back into the water. Several days later, the biologist nets a sample of 200 basses, of which 30 are tagged. How many basses are in the lake? You and your classmates will explore how the biologist can use sampling to describe patterns and to make generalizations about the entire population.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 6
Answer:
It is given that
A fishery biologist takes 500 basses from a lake, tags them, and then releases them back into the water. Several days later, the biologist nets a sample of 200 basses, of which 30 are tagged.
So,
The total number of basses = 500 + 200
= 700
The number of basses tagged = 30
So,
After netting, the number of basses = 700 – 30
= 670
Hence, from the above,
We can conclude that after the biologist nets 200 basses,
The total number of basses present are: 670

 Investigate Bivariate Data 1

Topic 4 GET READY!

Review What You Know!

Vocabulary

Choose the best term from the box to complete each definition.

Question 1.
____ is the change in y divided by the change in x.
Answer:
We know that,
“Slope” is the change in y divided by the change in x
Hence, from the above,
We can conclude that the best term to complete the given definition is: Slope

Question 2.
A relationship where for every x units of one quantity there are y units of another quantity is a ____
Answer:
We know that,
A relationship where for every x units of one quantity, there are y units of another quantity is a “Ratio”
Hence, from the above,
We can conclude that the best term to complete the given definition is: Ratio

Question 3.
The ____ is the horizontal line in a coordinate plane.
Answer:
We know that,
The “X-axis” is the horizontal line in a coordinate plane
Hence, from the above,
We can conclude that the best term to complete the given definition is: X-axis

Question 4.
The ___ is the vertical line in a coordinate plane.
Answer:
We know that,
The “Y-axis” is the vertical line in a coordinate plane
Hence, from the above,
We can conclude that the best term to complete the given definition is: Y-axis

Graphing Points
Graph and label each point on the coordinate plane.

Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 7

Question 5.
(-2, 4)
Answer:

Question 6.
(0, 3)
Answer:

Question 7.
(3, -1)
Answer:

Question 8.
(-4, -3)
Answer:

Finding Slope

Find the slope between each pair of points.

Question 9.
(4, 6) and (-2, 8)
Answer:
The given points are: (4, 6), (-2, 8)
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{8 – 6}{-2 – 4}\)
= \(\frac{2}{-6}\)
= –\(\frac{1}{3}\)
Hence, from the above,
We can conclude that the slope between the given points is: –\(\frac{1}{3}\)

Question 10.
(-1, 3) and (5,9)
Answer:
The given points are: (-1, 3), (5, 9)
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{9 – 3}{5 + 1}\)
= \(\frac{6}{6}\)
= 1
Hence, from the above,
We can conclude that the slope between the given points is: 1

Question 11.
(5, -1) and (-3, -7)
Answer:
The given points are: (5, -1), (-3, -7)
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{-7 + 1}{-3 – 5}\)
= \(\frac{-6}{-8}\)
= \(\frac{3}{4}\)
Hence, from the above,
We can conclude that the slope between the given points is: \(\frac{3}{4}\)

Writing Fractions as Percents

Question 12.
Explain how to write \(\frac{36}{60}\) as a percent.
Answer:
The given fraction is: \(\frac{36}{60}\)
We know that,
1 = 100%
So,
\(\frac{36}{60}\)
= \(\frac{36}{60}\) × 100%
= \(\frac{36 × 100%}{60}\)
= 60%
Hence, from the above,
We can conclude that the value of \(\frac{36}{60}\) as a percent is: 60%

Investigate Bivariate Data 2

Language Development

Complete the graphic organizer. Write the definitions of the terms in your own words. Use words or a sketch to show an example.

Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.1
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.2
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.3
Answer:

Topic 4 PICK A PROJECT

PROJECT 4A

What carnival games do you have a good chance of winning, and why?
PROJECT: BUILD A CARNIVAL GAME
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.5

PROJECT 4B
If you had a superpower, what would it be?
PROJECT: SUMMARIZE SUPERHERO DATA
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.6

PROJECT 4C
What makes a song’s lyrics catchy?
PROJECT: WRITE A SONG
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.7

PROJECT 4D
How does your dream job use math?
PROJECT: RESEARCH A CAREER
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.8

Lesson 4.1 Construct and Interpret Scatter Plots

Solve & Discuss It!

Luciana is starting a two-week social media campaign to attract new subscribers to Blaston, a music website for teens. She has the following data from her last campaign to help plan her strategy.

Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.9

Look for Relationships
How are the number of media posts and the number of subscribers related?
Answer:
The given data is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 9.9
If we observe the total data,
We can find that there is no particular pattern for the given data
But, if we observe the given data in parts, then
From 1 – 5 posts per day,
Social media posts per day ∝ New subscribers
From 8 – 10 posts per day,
Social media posts per day ∝ \(\frac{1}{New subscribers}\)
From 6 – 7 posts per day,
There is no pattern between the social media posts per day and the number of subscribers

Based on this data, what should be Luciana’s strategy for the new campaign?
Answer:
Based on the pattern of the given data (As mentioned above),
Luciana’s strategy for the new campaign must be:
The social media posts per day and the new subscribers must be in an increasing trend only

Investigate Bivariate Data 3

Focus on math practices
Use Structure What patterns do you see in the data from Luciana’s last social media campaign?
Answer:
If we observe the total data,
We can find that there is no particular pattern for the given data
But, if we observe the given data in parts, then
From 1 – 5 posts per day,
Social media posts per day ∝ New subscribers
From 8 – 10 posts per day,
Social media posts per day ∝ \(\frac{1}{New subscribers}\)
From 6 – 7 posts per day,
There is no pattern between the social media posts per day and the number of subscribers

Essential Question
How does a scatter plot show the relationship between paired data?
Answer:
The scatter diagram graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them. If the variables are correlated, the points will fall along a line or curve. The better the correlation, the tighter the points will hug the line.

Try It!
Luciana collects data about the number of entries and the ages of the subscribers who enter the concert giveaway.

Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.45

The point that represents the data in the fourth column has coordinates Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.4
Answer:
The given data is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.45
Now,
We know that,
The x-axis always represents the independent variables
The y-axis always represents the dependent variables
So,
From the given data,
The independent variable (x) is: Age
The dependent variable (y) is: Number of entries
We know that,
The ordered pair must be in the form of (x, y)
Hence, from the above,
We can conclude that the point that represents the data in the fourth column has coordinates (13, 9)

Convince Me!
Explain how Luciana would choose scales for the x-axis and y-axis.
Answer:
In a graph,
The scales for the x-axis and the y-axis is nothing but the rate of change between the values of x and y
Ex:
The given data is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.45
From the above data,
The scale for the x-axis is:
Rate of change between the values of x = 11 – 10 (or) 12 – 11 and so on
= 1
The scale for the y-axis is:
Rate of change between the values of y = 9 – 8 (or) 10 – 9
= 1
Hence, from the above,
We can conclude that
The scale for the x-axis is:
1 unit = 1 year
The scale for the y-axis is:
1 unit = 1 Entry

Try It!
Avery also tracks the number of minutes a player plays and the number of points the player scored. Describe the association between the two data sets. Tell what the association suggests.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.46
Answer:
It is given that
Avery also tracks the number of minutes a player plays and the number of points the player scored.
So,
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.46
Now,
From the given scatter plot,
We can observe that the overall pattern is in an increasing trend
But,
When we observe the number of points in the perspective of minutes,
The pattern is in clusters
Now,
At 4 minutes,
The number of points scored is: 0
At 6 and 8 minutes,
The number of points scored is: 2
Between 8 and 14 minutes,
The number of points scored is: 4
Between 10 and 16 minutes,
The number of points scored is: 6

KEY CONCEPT

A scatter plot shows the relationship, or association, between two sets of data.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.5
The y-values increase as the x-values increase.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.6
The y-values decrease as the x-values increase.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 10.7
There is no consistent pattern between the y-values and the x-values.

Do You Understand?

Question 1.
? Essential Question
How does a scatter plot show the relationship between paired data?
Answer:
The scatter diagram graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them. If the variables are correlated, the points will fall along a line or curve. The better the correlation, the tighter the points will hug the line.

Question 2.
Model with Math
Marcy always sleeps fewer than 9 hours each night and has never scored more than 27 points in a basketball game. A scatter plot suggests that the more sleep she gets, the more she scores. What scales for the axes might be best for constructing the scatter plot?
Answer:
It is given that
Marcy always sleeps fewer than 9 hours each night and has never scored more than 27 points in a basketball game. A scatter plot suggests that the more sleep she gets, the more she scores.
So,
The scales for the axes that might be best is:
For the x-axis:
It is given that Macy always sleeps fewer than 9 hours
So,
The scale might be: 1 unit starting from 9 to 24
For the y-axis:
It is given that Macy never scored more than 27 points in a basketball game
So,
The scale might be: 1 unit starting from 27 to the corresponding last value of x
Hence, from the above,
We can conclude that
For the x-axis,
The scale is:
1 unit = 1 hour
For the y-axis,
The scale is:
1 unit = 1 point

Question 3.
Construct Arguments Kyle says that every scatter plot will have a cluster, gap, and outlier. Is he correct? Explain.
Answer:
We know that,
A scatter plot might have a cluster, a gap, and an outlier or the association of any two but not all three are present
Hence, from the above,
We can conclude that Kyle is not correct

Do You Know How?

Question 4.
Phoebe constructs a scatter plot to show the data. What scales could she use for the x- and y-axes?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.1
Answer:
It is given that
Phoebe constructs a scatter plot to show the data.
Note:
The scatter plot is drawn only for the relations that are functions and we know that the rate of change is constant for a function
Now,
The given data is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.1
From the given data,
The scale she could use for the x-axis will be 1 unit
The scale she might use for the y-axis will be: 1 unit
Hence, from the above,
We can conclude that
The scale used for the x-axis is:
1 unit = 1 inch (Shoe size)
The scale used for the y-axis is:
1 unit = 1 inch (Height)

Question 5.
Germaine constructs a scatter plot to show how many people visit different theme parks in a month. Why might clusters and outliers be present?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.2
Answer:
It is given that
Germaine constructs a scatter plot to show how many people visit different theme parks in a month
Now,
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.2
From the given scatter plot,
We can observe that the graph is non-linear
We know that,
A cluster is a group of objects, numbers, data points (information), or even people that are located close together
An outlier is a value in a data set that is very different from the other values. That is, outliers are values unusually far from the middle
So,
From the given scatter plot,
We can observe that there are 2 points that are far from the pattern and those points are called “Outliers”
Since the scatter plot is non-linear, the points will be grouped together and the group of points is called “Clusters”

Practice & Problem Solving

Question 6.
Leveled Practice The table shows the racing times in minutes for the first two laps in a race. Complete the scatter plot.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.3
Answer:
It is given that
The table shows the racing times in minutes for the first two laps in a race
Now,
In the graph,
The x-axis represents: The racing times of Lap 1
The y-axis represents: The racing times of Lap 2
Hence,
The completed scatter plot with the x-axis and y-axis is:

Question 7.
The scatter plot represents the prices and number of books sold in a bookstore.
a. Identify the cluster in the scatter plot and explain what it means.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.4
Answer:
It is given that
The scatter plot represents the prices and number of books sold in a bookstore.
Now,
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 11.4
Now,
We know that,
A cluster is a group of objects, numbers, data points (information), or even people that are located close together
So,
From the above scatter plot,
We can observe that the clusters are present between the intervals of 10 books sold and 20 books sold

b. Generalize How does the scatter plot show the relationship between the data points? Explain.
Answer:
The scatter diagram graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them. If the variables are correlated, the points will fall along a line or curve. The better the correlation, the tighter the points will hug the line.

Question 8.
The table shows the monthly attendance in thousands at museums in one country over a 12-month period.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.5
a. Complete the scatter plot to represent the data.
Answer:
It is given that
The table shows the monthly attendance in thousands at museums in one country over a 12-month period.
Now,
The given data is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.5
Hence,
The representation of the scatter plot for the given data is:

b. Identify any outliers in the scatter plot.
Answer:
We know that,
A value that “lies outside” (is much smaller or larger than) most of the other values in a set of data is called an “Outlier”
Hence, from the above,
We can conclude that
The outliers in the scatterplot are at (12, 3), (6, 36)

c. What situation might have caused an outlier?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.6
Answer:
From part (b),
The outliers in the scatterplot are at (12, 3), (6, 36)
So,
From the given points,
We can conclude that the number of people is very low at that particular month to cause the situation of outliers

Question 9.
Higher-Order Thinking The table shows the number of painters and sculptors enrolled in seven art schools. Jashar makes an incorrect scatter plot to represent the data.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.9
a. What error did Jashar likely make?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.10
Answer:
It is given that
The table shows the number of painters and sculptors enrolled in seven art schools.
Now,
The given data is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.9
So,
From the given data,
We can observe that
The variable that will be on the x-axis (Independent variable) is: Number of painters
The variable that will be on the y-axis (Dependent variable) is: Number of sculptors
But,
From the scatter plot drawn by Jashar,
He interchanged the variables of the axes i.e., he took the independent variable at the y-axis and the dependent variable at the x-axis
Hence, from the above,
We can conclude that the error made by Jashar is the interchange of the variables of the axes

b. Explain the relationship between the number of painters and sculptors enrolled in the art schools.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.11
Answer:
From the given data,
We can observe that for the increase in painters, the number of sculptors also increases
Hence, from the above,
We can conclude that the relationship between the number of painters and sculptors enrolled in the art schools is:
Number of painters ∝ Number of sculptors

c. Reasoning Jashar’s scatter plot shows two possible outliers. Identify them and explain why they are outliers.
Answer:
We know that,
A value that “lies outside” (is much smaller or larger than) most of the other values in a set of data is called an “Outlier”
Now,
The scatter plot for the given data is:

Hence, from the above,
We can conclude that the two possible outliers identified by Jashar are: (11, 6), and (20, 45)

Assessment Practice

Use the scatter plot to answer 10 and 11.

Question 10.
Ten athletes in the Florida Running Club ran two races of the same length. The scatter plot shows their times. Select all statements that are true.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.12
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.13 Nine of the times for the first race were at least 16 seconds.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.13 Eight of the times for the second race were less than 17 seconds.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.13 There were seven athletes who were faster in the second race than in the first.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.13 There were three athletes who had the same time in both races.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.13 There were three athletes whose times in the two races differed by exactly 1 second.
Answer:
It is given that
Ten athletes in the Florida Running Club ran two races of the same length. The scatter plot shows their times.
Now,
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 12.12
Hence,
The correct statements about the given scatter plot is:

Question 11.
What was the greatest difference for a single runner in finishing times in the races?
A. 3 seconds
B. 4 seconds
C. 5 seconds
D. 7 seconds
Answer:
From the given scatter plot,
We can observe that
The lowest time a runner takes for completing a race is approximately 14 seconds
The highest time a runner takes for completing a race is approximately 17 seconds
So,
The greatest difference for a single runner in finishing times in the races is: 3 seconds
Hence, from the above,
We can conclude that option A matches the given situation

Lesson 4.2 Analyze Linear Associations

Solve & Discuss It!

Angus has a big test coming up. Should he stay up and study or go to bed early the night before the test? Defend your recommendation.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.1
Answer:
It is given that
Angus has a big test coming up
Now,
The relationship between the sleeping time and the percentage of marks is also given
Now,
From the given data,
We can observe that
If he went to bed early i.e., at 9:00, then he got 93%
If he studied until 11:00, then he got only 92%
Hence, from the above,
We can conclude that Angus has to go to bed early before the big test

Generalize
Can you make a general statement about which option leads to a better result?
Answer:
Generally, going to bed early will lead to better results before a test

Focus on math practices
Construct Arguments What other factors should Angus also take into consideration to make a decision? Defend your response.
Answer:
The other factors that Angus should also take into consideration when making a decision are:
A) Nature of the exam
B) Coverage of the topics for the particular exam
C) Number of revisions

? Essential Question
How can you describe the association of two data sets?
Answer:
Association (or relationship) between two variables will be described as strong, weak, or none; and the direction of the association may be positive, negative, or none

Try It!
Georgia and her classmates also measured their foot length. Use a pencil to find the trend line. Sketch the trend line for the scatter plot.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.2
Answer:
It is given that
Georgia and her classmates also measured their foot length
Hence,
The representation of a trend line for the given scatter plot is:

Try It!
For each scatter plot, identify the association between the data. If there is no association, state so.
a.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.3

Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.3
From the above scatter plot,
We can observe that the points are all scattered
Hence, from the above,
We can conclude that the given scatter plot has a weaker association

b.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.4
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.4
From the given scatter plot,
The points are all in a non-linear shape
Hence, from the above,
We can conclude that the given scatter plot has a non-linear association
c.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.5
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.5
From the scatter plot,
We can observe that the points are all scattered
Hence, from the above,
We can conclude that the given scatter plot has a weaker association

KEY CONCEPT

Scatter plots can show a linear association, a nonlinear association, or no association. For scatter plots that suggest a linear association, you can draw a trend line to show the association. You can assess the strength of the association by looking at the distances of plotted points from the trend line.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.6

Do You Understand?

Question 1.
? Essential Question How can you describe the relationship between the two sets of data?
Answer:
Association (or relationship) between two variables will be described as strong, weak, or none; and the direction of the association may be positive, negative, or none

Question 2.
Look for Relationships How does a trend line describe the strength of the association?
Answer:
The straight line is a trend line, designed to come as close as possible to all the data points. The trend line has a positive slope, which shows a positive relationship between X and Y. The points in the graph are tightly clustered about the trend line due to the strength of the relationship between X and Y.

Question 3.
Construct Arguments How does the scatter plot of a nonlinear association differ from that of a linear association?
Answer:
Scatterplots with a linear pattern have points that seem to generally fall along a line while nonlinear patterns seem to follow along some curve. Whatever the pattern is, we use this to describe the association between the variables.

Do You Know How?

Question 4.
Describe the association between the two sets of data in the scatter plot.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.7
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.7
From the given scatter plot,
We can observe that all the points are tightly hugged by a trend line
Hence, from the above,
We can conclude that the given scatter plot has a stronger association

Question 5.
Describe the association between the two sets of data in the scatter plot.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.8
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.8
From the given scatter plot,
We can observe that the points are all in a non-linear shape and are closely connected
Hence, from the above,
We can conclude that the given scatter plot has a non-linear association

Practice & Problem Solving

Scan for Multimedia

Question 6.
The scatter plot shows the average heights of children ages 2-12 in a certain country. Which line is the best model of the data?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 13.9
Answer:
It is given that
The scatter plot shows the average heights of children ages 2-12 in a certain country.
Now,
The best line in the given scatter plot is that line that tightly hugs the maximum points in a scatter plot
Hence, from the above,
We can conclude that line m is the best model of the given data

Question 7.
Does the scatter plot shows a positive, a negative, or no association?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.1
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.1
From the given scatter plot,
We can observe that as the value of x increases, the value of y also increases
Hence, from the above,
We can conclude that the given scatter plot has a positive association

Question 8.
Determine whether the scatter plot of the data for the following situation would have a positive or negative linear association.
time working and amount of money earned
Answer:
The given situation is:
Time working and amount of money earned
We know that,
The total amount of work done = Number of days × The amount earned for the work done
Let us suppose the number of days is constant
So,
The total amount of work done ∝ The amount earned for the work done
So,
The more time a person works, the more money that person will earn
Hence, from the above,
We can conclude that the scatter plot of the given data has a positive linear association

Question 9.
Describe the relationship between the data in the scatter plot.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.2
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.2
From the given scatter plot,
We can observe that the data in the scatter plot has a decreasing trend with the strong association of data with each other
Hence, from the above
We can conclude that the given scatter plot has a negative linear association

Question 10.
Describe the relationship between the data in the scatter plot.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.3
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.3
From the given scatter plot,
We can observe that all the points are in a cyclic fashion
Hence, from the above,
We can conclude that the given scatter plot has a non-linear association

Question 11.
Higher-Order Thinking Describe a real situation that would fit the relationship described.
a. A strong, positive association
Answer:
The real-life examples for a strong, positive association are:
A) The more time you spend running on a treadmill, the more calories you will burn.
B) Taller people have larger shoe sizes and shorter people have smaller shoe sizes.
C) The longer your hair grows, the more shampoo you will need.
D) The less time I spend marketing my business, the fewer new customers I will have.
E) The more hours you spend in direct sunlight, the more severe your sunburn.

b. A strong, negative association
Answer:
The real-life examples for a strong, negative association are:
A) A student who has many absences has a decrease in grades.
B) As the weather gets colder, air conditioning costs decrease.
C) If a train increases speed, the length of time to get to the final point decreases.
D) If a chicken increases in age, the number of eggs it produces decreases.
E) If the sun shines more, a house with solar panels requires less use of other electricity.

Question 12.
A sociologist is studying how sleep affects the amount of money a person spends. The scatter plot shows the results of the study. What type of association does it show between the amount of sleep and money spent?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.4
Answer:
It is given that
A sociologist is studying how sleep affects the amount of money a person spends. The scatter plot shows the results of the study
Now,
From the given scatter plot,
We can observe that the data that is related to the amount of sleep and the amount of money spent is in a cyclic fashion
Hence, from the above,
We can conclude that the association does it show between the amount of sleep and money spent is: Non-linear association

Assessment Practice

Question 13.
Which paired data would likely show a positive association? Select all that apply.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Population and the number of schools
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Hair length and shoe size
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Number of people who carpool to work and money spent on gas
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Hours worked and amount of money earned
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Time spent driving and amount of gas in the car
Answer:
We know that,
A positive association is an association that as the value of x increases, the value of y also increases
Hence,
The paired data that would likely show a positive association is

Question 14.
Which paired data would likely show a negative association? Select all that apply.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Population and the number of schools
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Hair length and shoe size
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Number of people who carpool to work and money spent on gas
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Hours worked and amount of money earned
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.5 Time spent driving and amount of gas in the car
Answer:
We know that,
A negative association is an association that as the value of x increases, the value of y also decreases
Hence,
The paired data that would likely show a negative association is:

Lesson 4.3 Use Linear Models to Make Predictions

Solve & Discuss It!

Bao has a new tracking device that he wears when he exercises. It sends data to his computer. How can Bao determine how long he should exercise each day if he wants to burn 5,000 Calories per week?
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 14.6
Answer:
It is given that
Bao has a new tracking device that he wears when he exercises. It sends data to his computer
Now,
It is also given that Bao wants to burn 5,000 calories per week
So,
The number of calories Bao wants to burn per day = \(\frac{5,000}{7}\)
= 714.2 calories
= 714 calories
≅ 720 calories
Now,
From the given scatter plot,
We can observe that
For approximately 720 calories to burn, Bao has to exercise 80 – 90 minutes each day
Hence, from the above,
We can conclude that Bao should exercise 80 – 90 minutes each day if he wants to burn 5,000 Calories per week

Focus on math practices

Reasoning Suppose another set of data were plotted with a trend line passing through (25, 100) and (80, 550). Would this indicate that more or fewer calories were burned per minute? Explain.
Answer:

? Essential Question
How do linear models help you to make a prediction?
Answer:
While linear models do not always accurately represent data, and this occurs when actual data does not clearly show a relationship between its two variables, linear models are helpful in determining the future points of data, the expected points of data, and the highest possible accuracy of data.

Try It!

Assuming the trend shown in the graph continues, use the equation of the trend line to predict average fuel consumption in miles per gallon in 2025.
The equation of the trend line is y = Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 16.1x + Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 16.1. In 2025, the average fuel consumption is predicted to be about mpg.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 16.2
Answer:
The given scatter plot is:
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 16.2
From the scatter plot,
We can observe that
The initial value (y-intercept) is: 15
Now,
We know that,
The equation of the line in the slope-intercept form is:
y = mx + b
Where,
m is the slope
b is the initial value (or) y-intercept
Now,
To find the slope,
The points from the given scatter plot is: (15, 21), (30, 24)
Now,
Compare the given points with (x1, y1), (x2, y2)
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{24 – 21}{30 – 15}\)
= \(\frac{1}{5}\)
So,
The equation of the line is:
y = 0.20x + 15
Now,
The average fuel consumption in 2025 is:
y = 0.20 (2025 – 1980) + 15
y = 0.20 (45) + 15
y = 9 + 15
y = 24 mpg
Hence, from the above,
We can conclude that
The equation of the trend line is:
y = 0.20x + 15
In 2025, the average fuel consumption is predicted to be about 24 mpg

Convince Me!
Why can you use a linear model to predict the y-value for a given x-value?
Answer:
We can use the regression line to predict values of Y was given values of X. For any given value of X, we go straight up to the line and then move horizontally to the left to find the value of Y. The predicted value of Y is called the predicted value of Y, and is denoted Y’.

Try It!

A smoothie café has the ingredients needed to make 50,000 smoothies on a day when the high temperature is expected to reach 90°F. Should the café employees expect to have enough ingredients for the day’s smoothie sales? Explain.
Answer:

KEY CONCEPT
Scatter plots can be used to make predictions about current or future trends.
Look for the corresponding y-value for a given x-value.
Envision Math Common Core Grade 8 Answer Key Topic 4 Investigate Bivariate Data 16.3

Find the equation of the trend line and find the y-value of a given x-value.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 16.4

Do You Understand?

Question 1.
?Essential Question How do linear models help you to make a prediction?
Answer:
While linear models do not always accurately represent data, and this occurs when actual data does not clearly show a relationship between its two variables, linear models are helpful in determining the future points of data, the expected points of data, and the highest possible accuracy of data.

Question 2.
Model with Math
How do you find the equation of a linear model when you are given the graph but not given the equation?
Answer:
To simplify what has already been said, the easiest way to find the equation of a line is to look for the x and y-intercepts.
One point will be (x, 0) and the other will be (0, y), where x and y are numerical values.
The slope is simply
m = \(\frac{y}{x}\).
When you have the y-intercept, (0, y),
you can use the form
y = mx + b to find the equation for the line.
Consequently, with the notation used, you can represent this as
y=\(\frac{y}{x}\)x + b
where b is the value from (0, y)
x is the value from (x, 0)

Question 3.
Reasoning Can the linear model for a set of data that is presented in a scatter plot always be used to make a prediction about any x-value? Explain.
Answer:
Yes, we can use the linear model to predict values of Y was given values of X. For any given value of X, we go straight up to the line and then move horizontally to the left to find the value of Y. The predicted value of Y is called the predicted value of Y, and is denoted Y’.

Do You Know How?

Question 4.
The graph shows a family’s grocery expenses based on the number of children in the family,
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.1
a. Using the slope, predict the difference in the amount spent on groceries between a family with five children and a family with two children.
Answer:
It is given that
The graph shows a family’s grocery expenses based on the number of children in the family,
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.1
Now,
From the given scatter plot,
The pair that represents the amount spent on groceries in a family with five children is: (5, 175)
The pair that represents the amount spent on groceries in a family with two children is: (2, 140)
Now,
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{140 – 175}{2 – 5}\)
Slope = \(\frac{-35}{-3}\)
Slope = \(\frac{35}{3}\)
Hence, from the above,
We can conclude that using the slope, the difference in the amount spent on groceries between a family with five children and a family with two children is: \(\frac{35}{3}\)

b. How many children can you predict a family has if the amount spent on groceries per week is $169.47?
Answer:
From the given scatter plot,
The trend line equation is:
y = 21.08x + 85.15
Now,
It is given that the amount spent on groceries per week is $169.47
So,
169.47 = 21.08x + 85.15
21.08x = 169.47 – 85.15
21.08x = 84.32
x = \(\frac{84.32}{21.08}\)
x = 4
Hence, from the above,
We can predict 4 children in a family if he has the amount spent on groceries per week is $169.47

Practice & Problem Solving

Question 5.
Leveled Practice The scatter plot shows the number of people at a fair based on the outside temperature. How many fewer people would be predicted to be at the fair on a 100°F day than on a 75°F day?
The slope is Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.2
For each degree that the outside temperature increases, the fair attendance decreases by Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.2 thousand people.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.34
The difference between 75°F and 100°F is Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.2 °F.
-0.16 . Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.2 = Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.2
About Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.2 thousand fewer people are predicted to be at the fair on a 100°F day than on a 75°F day.
Answer:
It is given that
The scatter plot shows the number of people at a fair based on the outside temperature
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.34
Now,
We know that,
The equation of the trend line that is passing through two points is:
y = mx + b
Where,
m is the slope
b is the initial value (or) y-intercept
Now,
To find the slope,
The given points are: (75, 10K), (100, 6K)
Where,
K is 1000
Now,
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{6K – 10K}{100 – 75}\)
= –\(\frac{4,000}{25}\)
= -160
So,
The equation of the trend line is:
y = -160x + b
Substitute (100, 6K) in the above equation
So,
6K = -160 (100) + b
6K + 16K = b
b = 22K
So,
The equation of the trend line is:
y = -160x + 22,000
Now,
At 75° F,
y = -160 (75) + 22,000
y = 10,000
At 100° F,
y = -160 (100) + 22,000
y = 6,000
Hence,
The difference of the people between 75° F and 100° F = 10,000 – 6,000
= 4,000
The difference between 100° F and 75° F = 25° F

Question 6.
Make Sense and Persevere If x represents the number of years since 2000 and y represents the gas price, predict what the difference between the gas prices in 2013 and 2001 is? Round to the nearest hundredth.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.3
Answer:
It is given that
x represents the number of years since 2000 and y represents the gas price,
Now,
We know that,
The equation of the trend line in the slope-intercept form is:
y = mx + b
Where,
m is the slope
b is the y-intercept
Now,
To find the slope of the trend line,
The given points are: (7, 3), (12, 4)
Now,
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{4 – 3}{12 – 7}\)
Slope = \(\frac{1}{5}\)
So,
y = \(\frac{1}{5}\)x + b
Now,
Substitute (7, 3) or (12, 4) in the above equation
So,
3 = \(\frac{1}{5}\) (7) + b
\(\frac{8}{5}\) = b
So,
The equation of the trend line is:
5y = x + 8
Now,
The gas prices in 2001 is:
5y = 1 + 8
y = \(\frac{9}{5}\)
y = $1.40
The gas prices in 2013 is:
5y = 13 + 8
y = \(\frac{21}{5}\)
y = $4.20
So,
The difference between the gas prices in 2013 and 2001 = $4.20 – $1.40
= $2.80
Hence, from the above,
We can conclude that the difference between the gas prices in 2013 and 2001 is: $2.80

Question 7.
Make Sense and Persevere If x represents the number of months since the beginning of 2016, and y represents the total precipitation to date, predict the amount of precipitation received between the end of March and the end of June.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.4
Answer:
It is given that
x represents the number of months since the beginning of 2016, and y represents the total precipitation to date
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.4
Now,
From the given scatter plot,
We can observe that the trend line starts from the origin
So,
The equation of the trend line that is passing through the origin is:
y = mx
where,
m is the slope
Now,
To find the slope.
The given points are: (2, 10), (10, 40)
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{40 – 10}{10 – 2}\)
= \(\frac{30}{8}\)
= \(\frac{15}{4}\)
So,
The equation of the trend line is:
y = \(\frac{15}{4}\)x
Now,
At the end of the march,
The amount of precipitation is:
y = \(\frac{15}{4}\) (4)
y = 15 in
At the end of June,
The amount of precipitation is:
y = \(\frac{15}{4}\) (6)
y = \(\frac{45}{2}\)
y = 22.5 inches
So,
The amount of precipitation between the end of March and the end of June = 22.5 – 15
= 7.5 in
Hence, from the above,
We can conclude that the amount of precipitation between the end of March and the end of June is: 7.5 in

Question 8.
The scatter plot shows a hiker’s elevation above sea level over time. The equation of the trend line shown is y = 8.77x + 686. To the nearest whole number, predict what the hiker’s elevation will be after 145 minutes.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.5
Answer:
It is given that
The scatter plot shows a hiker’s elevation above sea level over time.
The equation of the trend line shown is
y = 8.77x + 686.
Where,
8.77 is the slope
686 is the initial value (or) y-intercept
Now,
From the graph,
We can observe that
The x-axis variable – Time
The y-axis variable – Elevation
So,
The hiker’s elevation after 145 minutes is:
y = 8.77 (145) + 686
y = 1,957.65 ft
Hence, from the above,
We can conclude that the hiker’s elevation after 145 minutes will be: 1,957.65 ft

Question 9.
Make Sense and Persevere The graph shows the number of gallons of water in a large tank as it is being filled. Based on the trend line, predict how long it will take to fill the tank with 375 gallons of water.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.6
Answer:
It is given that
The graph shows the number of gallons of water in a large tank as it is being filled
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.6
Now,
From the given scatter plot,
We can observe that
The initial value (or) y-intercept is: 15
Now,
We know that,
The equation of the trend line that has the initial value is:
y = mx + b
Where,
m is the slope
b is the y-intercept (or) initial value
Now,
To find the slope,
The required points are: (1, 30), (0, 15)
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{15 – 30}{0 – 1}\)
= \(\frac{-15}{-1}\)
= 15
So,
The equation of the trend line is:
y = 15x + 15
Now,
The time taken to fill 375 gallons of water is:
375 = 15x + 15
15x = 375 – 15
15x = 360
x = \(\frac{360}{15}\)
x = 24 minutes
Hence, from the above,
We can conclude that the time taken to fill 375 gallons of water is: 24 minutes

Question 10.
Higher-Order Thinking The graph shows the temperature, y, in a freezer x minutes after it was turned on. Five minutes after being turned on, the temperature was actually three degrees from what the trend line shows. What values could the actual temperature be after the freezer was on for five minutes?
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.7
Answer:
It is given that
The graph shows the temperature, y, in a freezer x minutes after it was turned on. Five minutes after being turned on, the temperature was actually three degrees from what the trend line shows.
Now,
From the given scatter plot,
We can observe that,
At 5 minutes of time, the freezer temperature is 15°F
So,
At x = 5, y = 15
But,
According to the given information
At x = 5, y = 15 + 3
So,
y = 18°F
Hence, from the above,
We can conclude that the actual temperature after the freezer was on for five minutes is: 18°F

Assessment Practice

Question 11.
The graph shows the altitude above sea level of a weather balloon over time. The trend line passes through the points (0, 453) and (10, 359). Which statements about the graph are true?
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.8 The data show a positive correlation.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.8 The trend line is -9.4x – 453.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.8 In general, the balloon is losing altitude.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.8 The weather balloon started its flight at about 455 feet above sea level.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.9
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.8 After 4 minutes, the weather balloon had an altitude of about 415 feet above sea level.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 17.8 After 395 minutes, the weather balloon had an altitude of about 8 feet above sea level.
Answer:
Let the given options be named as A, B, C, D, E and F respectively
It is given that
The graph shows the altitude above sea level of a weather balloon over time.
The trend line passes through the points (0, 453) and (10, 359)
We know that,
The equation of the trend line that is passing through two points is:
y = mx + b
Where,
m is the slope
b is the initial value (or) y-intercept
We know that
The “y-intercept” is the value of y when x= 0
Now,
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{359 – 453}{10 – 0}\)
= \(\frac{-94}{10}\)
= -9.4
So,
The equation of the trend line is:
y = -9.4x + 453
Hence, from the above,
We can conclude that options C, D, and E matches the given situation

Topic 4 MID-TOPIC CHECKPOINT

Question 1.
Vocabulary How can you use a trend line to determine the type of linear association for a scatter plot? Lesson 4.2
Answer:
The straight line is a trend line, designed to come as close as possible to all the data points. The trend line has a positive slope, which shows a positive relationship between X and Y. The points in the graph are tightly clustered about the trend line due to the strength of the relationship between X and Y.

The scatter plot shows the amount of time Adam spent studying and his test scores. Use the scatter plot for Items 2-4.

Question 2.
What relationship do you see between the amount of time spent studying and the test scores? Is the relationship linear? Lesson 4.1
A. In general, Adam scores higher on a test when he spends more time studying. There is not a linear relationship.
B. In general, Adam scores higher on a test when he spends more time studying. There is a positive linear relationship.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 20.1
C. In general, Adam scores lower on a test when he spends more time studying. There is a negative linear relationship.
D. In general, Adam scores lower on a test when he spends more time studying. There is no relationship.
Answer:
It is given that
The scatter plot shows the amount of time Adam spent studying and his test scores
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 20.1
From the given scatter plot,
We can observe that
The association or correlation is positive and there is a linear relationship
Adam is scoring higher on a test when he is studying for more hours
Hence, from the above,
We can conclude that option B matches the given situation

Question 3.
Use the y-intercept and the point (4,90) from the line on the scatter plot. What is the equation of the linear model? Lesson 4.3
Answer:
The given scatter plot is (From Question 2):
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 20.1
Now,
From the given scatter plot,
We can observe that
The initial value (or) y-intercept is: 60
We know that,
The “y-intercept” is the value of y when x = 0
So,
The points required to find the equation of the scatter plot is: (0, 60), (4, 90)
We know that,
The equation of the trend line that has y-intercept is:
y = mx + b
Where,
m is the slope
b is the initial value (or) y-intercept
Now,
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{90 – 60}{4 – 0}\)
= \(\frac{30}{4}\)
= \(\frac{15}{2}\)
So,
The equation of the trend line is:
y = \(\frac{15}{2}\)x + 60
Hence, from the above,
We can conclude that the equation of the linear line is:
y = \(\frac{15}{2}\)x + 60

Question 4.
Predict Adam’s test score when he studies for 6 hours. Lesson 4.3
Answer:
We know that,
From the given scatter plot,
The variable on the x-axis is: Time
The variable on the y-axis is: Test scores
Now,
From Problem 3,
The equation of the trend line is:
y = \(\frac{15}{2}\)x + 60
At 6 hours,
y = \(\frac{15}{2}\) (6) + 60
y = 105
Hence, from the above,
We can conclude that Adam’s test score is 105 when he studies for 6 hours

Question 5.
Describe the relationship between the data in the scatter plot. Lesson 4.2
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 20.2
Answer:
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 20.2
From the above scatter plot,
We can observe that as the value of x increases, the value of y decreases
Hence, from the above,
We can conclude that the given scatter plot has the negative association

Question 6.
The scatter plot shows the mean annual temperature at different elevations. Select all the observations that are true about the scatter plot. Lesson 4.1
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 22.1 The majority of the elevations are in a cluster between 1,250 meters and 2,250 meters.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 22.1 There is a gap in the data between 500 meters and 1,250 meters.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 23.1
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 22.1 There is an outlier at about (50, 21).
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 22.1 In general, the mean annual temperature decreases as the elevation increases.
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 22.1 Because there is a gap in the values, there is no association between the temperature and elevation.
Answer:
Let the given options be named as A, B, C, D, and E
It is given that
The scatter plot shows the mean annual temperature at different elevations
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 23.1
From the given scatter plot,
We can observe that
There is a cluster between 1,250 m and 2,250m
There is a gap between 500m and 1,250m
In general, the mean annual temperature decreases as the elevation increases.
Because there is a gap in the values, there is no association between the temperature and elevation.
Hence, from the above,
We can conclude that A, B, D, and E matches the given situation
How well did you do on the mid-topic checkpoint? Fill in the stars. Envision Math Common Core 8th Grade Answers Topic 4 Investigate Bivariate Data 24.1

Topic 4 MID-TOPIC PERFORMANCE TASK

A pitcher’s ERA (earned run average) is the average number of earned runs the pitcher allows every 9 innings pitched. The table shows the ERA and the number of wins for starting pitchers in a baseball league.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 26.1

PART A
Construct a scatter plot of the data in the table.
Answer:
It is given that
A pitcher’s ERA (earned run average) is the average number of earned runs the pitcher allows every 9 innings pitched. The table shows the ERA and the number of wins for starting pitchers in a baseball league.
Now,
The given table is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 26.1
Hence,
The representation of the scatter plot for the given data is:

PART B
Identify the association between the data. Explain the relationship between ERA and the number of wins shown in the scatter plot.
Answer:
From the above scatter plot,
We can observe that
As the value of x increases, the value of y decreases
Hence, from the above,
We can conclude that the relationship between ERA and the number of wins as shown in the above scatter plot is a “Negative Correlation”

PART C
Draw a trend line. Write an equation of the linear model. Predict the number of wins of a pitcher with an ERA of 6.
Answer:
We know that,
The equation of the trend line between two points is:
y = mx + b
Where,
m is the slope
b is the initial value (or) y-intercept
Now,
To find the slope,
The points are: (5, 4), (2, 10)
Now,
Compare the given points with (x1, y1), (x2, y2)
Now,
We know that,
Slope = y2 – y1 / x2 – x1
So,
Slope = \(\frac{10 – 4}{2 – 5}\)
= –\(\frac{6}{3}\)
= -2
So,
The equation of the trend line is:
y = -2x + b
Now,
Substitute (5, 4) in the above equation
So,
4 = -2 (5) + b
4 + 10 = b
b = 14
So,
The equation of the trend line is:
y = -2x + 14
Now,
From the given table,
We can observe that
The x-axis variable is: ERA
The y-axis variable is: The number of wins
So,
For x = 6,
y = -2 (6) + 14
y = 14 – 12
y = 2
Hence, from the above,
We can conclude that the number of wins of a pitcher with an ERA of 6 is: 2

Lesson 4.4 Interpret Two-Way Frequency Tables

Explore It!
The owners of a ski resort want to know which is more popular, skiing or snowboarding. The resort conducts a poll, asking visitors their age and which activity they prefer. The results are shown in the table.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 26.2

A. Use the table to describe the visitors polled.
Answer:
It is given that
The owners of a ski resort want to know which is more popular, skiing or snowboarding. The resort conducts a poll, asking visitors their age and which activity they prefer. The results are shown in the table.
Now,
From the given table,
We can observe that the visiters polled are of the age below 35 and above 35
The activities for which the visitors polled are: Skiing, Snowboarding

B. What information can the owners of the resort determine from the data in the table?
Answer:
From the given table,
We can observe that
The number of visitors that had polled for Skiing and snowboarding
Hence, from the above,
We can conclude that the information the owners of the resort determine from the data in the table is the number of visitors that had polled for Skiing and Snowboarding

C. Make a statement that is supported by the data.
Answer:
The statement that is supported by the given data is:
The number of visitors that are over 35 years is the majority who polled for Skiing

Focus on math practices
Model with Math
How else might you display the data to show the relationship between people’s ages and which activity they prefer?
Answer:
The other way to display the data to show the relationship between people’s ages and the activity they prefer is:

Essential Question
How does a two-way frequency table show the relationships between sets of paired data?
Answer:
Two-way frequency tables are a visual representation of the possible relationships between two sets of categorical data. The categories are labeled at the top and the left side of the table, with the frequency (count) information appearing in the four (or more) interior cells of the table.

Try It!
A weatherman asks 75 people from two different cities if they own rain boots. Complete the two-way frequency table to show the results of the survey.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 27.1
Answer:
It is given that
A weatherman asks 75 people from two different cities if they own rain boots.
So,
The total number of people who say whether they own rain boots or not are: 75
So,
(The people who say yes + The people who say no)City A + (The people who say yes + the people who say no)City B = 75
Hence,
The complete two-way frequency table that shows the results of the survey is:

Convince Me!
What pattern do you see in the two-way frequency table?
Answer:
Two-way frequency tables are a visual representation of the possible relationships between two sets of categorical data. The categories are labeled at the top and the left side of the table, with the frequency (count) information appearing in the four (or more) interior cells of the table.

Try It!
One hundred students were asked how they traveled to school. Of the girls, 19 rode in a car, 7 rode the bus, and 27 took the train. Of the boys, 12 took the train, 25 rode in a car, and 10 rode the bus. Construct a two-way frequency table. Then tell which mode of transportation is the most popular. Explain.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 27.2
Answer:
It is given that
One hundred students were asked how they traveled to school. Of the girls, 19 rode in a car, 7 rode the bus, and 27 took the train. Of the boys, 12 took the train, 25 rode in a car, and 10 rode the bus
So,
The complete two-way frequency table for the given situation is:

Now,
From the above, two-way frequency table,
We can observe that more number of people preferred car mode of transportation
Hence, from the above,
We can conclude that the car mode of transportation is the most popular

KEY CONCEPT
A two-way frequency table displays the relationship between paired categorical data. You can interpret the data in the table to draw conclusions.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 27.3

Do You Understand?

Question 1.
?Essential Question How does a two-way frequency table show the relationship between sets of paired categorical data?
Answer:
Two-way frequency tables are a visual representation of the possible relationships between two sets of categorical data. The categories are labeled at the top and the left side of the table, with the frequency (count) information appearing in the four (or more) interior cells of the table.

Question 2.
Model with Math
How do you decide where to start filling in a two-way frequency table when some of the data are already there?
Answer:
In a two-way frequency table, when there is already data present,
You have to start filling in where there is more data in the table so that all the frequencies can be counted easily and filling of the frequency table will also be fast

Question 3.
Use Structure How can you use the structure of a two-way frequency table to complete it?
Answer:
The steps that are used to complete the two-way frequency table is:
Step 1:
Identify the variables. There are two variables of interest here: the commercial viewed and opinion
Step 2:
Determine the possible values of each variable. For the two variables, we can identify the following possible values
Step 3:
Set up the table
Step 4:
Fill in the frequencies

Do You Know How?

Question 4.
A basketball coach closely watches the shots of 60 players during basketball tryouts. Complete the two-way frequency table to show her observations.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.1
Answer:
It is given that
A basketball coach closely watches the shots of 60 players during basketball tryouts.
So,
Underclassmen + Upperclassmen = 60
Hence,
The complete two-way frequency table that shows the basketball coach’s observations is:

Question 5.
Do the data in the two-way frequency table support the following statement? Explain.
There are more middle school students who wear glasses than high school students who wear contacts.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.2
Answer:
The given statement is:
There are more middle school students who wear glasses than high school students who wear contacts.
Now,
The given two-way frequency table is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.2
From the given two-way frequency table,
The number of middle school students who wear glasses is: 13
The number of high school students who wear contacts is: 20
So,
The number of middle school students who wear glasses < The number of high school students who wear contacts
Hence, from the above,
We can conclude that the given statement can’t be supported

Practice & Problem Solving

Leveled Practice in 6-8, complete the two-way frequency tables.

Question 6.
You ask 70 of your classmates if they have any siblings. Complete the two-way frequency table to show the results of the survey.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.3
Answer:
It is given that
You ask 70 of your classmates if they have any siblings
So,
(The number of boys and girls who have siblings) + (The number of girls who do not have siblings) = 70
Hence,
The complete two-way frequency table that shows the survey results is:

Question 7.
A company surveyed 200 people and asked which car model they preferred. Complete the two-way frequency table to show the results of the survey.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.4
Answer:
It is given that
A company surveyed 200 people and asked which car model they preferred
So,
(The number of males and females who preferred 2-door car model) + (The number of males and females who preferred 4-door car model) = 200
Hence,
The complete two-way frequency table that shows the results of the survey is:

Question 8.
Make Sense and Persevere
You ask 203 of your classmates how they feel about the school year being made longer. Complete the two-way frequency table to show the results of the survey.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.5
Answer:
It is given that
You ask 203 of your classmates how they feel about the school year being made longer
So,
6th Grade students + 7th Grade students + 8th Grade students = 203
Hence,
The complete two-way frequency table that shows the complete survey results is:

Question 9.
Students at a local school were asked, “About how many hours do you spend on homework each week?” The two-way frequency table shows the results of the survey. Classify the statement below as true or false. Explain.
More students study for 5 to 6 hours than for 1 to 2 hours.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.6
Answer:
It is given that
The two-way frequency table shows the results of the survey.
Now,
The given statement is:
More students study for 5 to 6 hours than for 1 to 2 hours.
Now,
The given two-way frequency table is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.6
From the given two-way frequency table,
We can observe that
The number of students who study for 5 – 6 hours is: 104
The number of students who study for 1 – 2 hours is: 147
So,
The number of students who study for 1 – 2 hours > The number of students who study for 5 – 6 hours
Hence, from the above,
We can conclude that the given statement is false

Question 10.
Higher-Order Thinking Demi and Margaret record the weather in their respective cities on weekend days over the summer. a. Construct a single, two-way frequency table to show the results.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.7
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.8
Answer:
It is given that
Demi and Margaret record the weather in their respective cities on weekend days over the summer
Now,
The given information regarding the given situation is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 30.8
Let the struck lines be the number of times that have no rain
Let the non-struck lines be the number of lines that have rain
Hence,
The complete two-way frequency table that shows the results is:

b. Which day saw the least rain? Explain.
Answer:
The condition for the least rain is: The number of times rain occurs + The number of times that no rain occurs
Hence, from the above,
We can conclude that Saturday saw the least rain

Assessment Practice

Question 11.
At one point last year, the local animal shelter had only cats and dogs. There were 74 animals in all. Of the cats, 25 were male and 14 were female. Of the dogs, 23 were male and 12 were female.
PART A
Construct a two-way frequency table of
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 40.1
Answer:
It is given that
At one point last year, the local animal shelter had only cats and dogs. There were 74 animals in all. Of the cats, 25 were male and 14 were female. Of the dogs, 23 were male and 12 were female.
Hence,
The complete two-way table that shows the survey results is:

PART B
For which gender, male or female, is there the data.
a greater need for pet adoption? Explain.
A. There are almost twice as many female pets, so there is a greater need for people to adopt female dogs and cats.
B. There are almost twice as many male pets, so there is a greater need for people to adopt male dogs and cats.
C. There are almost twice as many female pets, so there is a greater need for people to adopt male dogs and cats.
D. There are almost twice as many male pets, so there is a greater need for people to adopt female dogs and cats.
Answer:
From part (A),
the two-way frequency table that matches the given situation is:

So,
From the above two-way frequency table,
We can observe that
There are almost twice as males as females
Hence, from the above,
We can conclude that option D matches the given situation perfectly

Lesson 4.5 Interpret TwoWay Relative Frequency Tables

Solve & Discuss It!

Mr. Day’s math class asked 200 cell phone owners which size phone they prefer. They presented the results in a two-way frequency table. How can you use the data to compare the percent of students who chose the small screen to the percent of adults who chose the small screen?
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 42.1
Answer:
It is given that
Mr. Day’s math class asked 200 cell phone owners which size phone they prefer. They presented the results in a two-way frequency table
Now,
From the given two-way frequency table,
We can observe that
The number of students who chose the small screen is: 48
The number of adults who chose the small screen is: 18
Now,
The percent of students who chose the small screen = \(\frac{The number of small screens chosen by the students}{The total number of screens}\) × 100
= \(\frac{48}{200}\) × 100
= 24%
The percent of adults who chose the small screen = \(\frac{The number of small screens chosen by the adults}{The total number of screens}\) × 100
= \(\frac{18}{200}\) × 100
= 9%
So,
The percent of students who chose the small screen to the percent of adults who chose the small screen
= \(\frac{9}{24}\) × 100
= \(\frac{9 × 100}{24}\)
= 37.5%
Hence, from the above,
We can conclude that the percent of students who chose the small screen to the percent of adults who chose the small screen is: 37.5%

Make Sense and Persevere
How do two-way frequency tables allow you to interpret relationships between categorical data using rows and columns?
Answer:
Two-way frequency tables are a visual representation of the possible relationships between two sets of categorical data. The categories are labeled at the top and the left side of the table, with the frequency (count) information appearing in the four (or more) interior cells of the table.

Focus on math practices
Make Sense and Persevere How does know a percentage change the way you interpret the results?
Answer:
First: work out the difference (increase) between the two numbers you are comparing. Then: divide the increase by the original number and multiply the answer by 100.
So,
% increase = Increase ÷ Original Number × 100.
If your answer is a negative number, then this is a percentage decrease.

? Essential Question
What is the advantage of a two-way relative frequency table for showing relationships between sets of paired data?
Answer:
Two-way relative frequency tables show us percentages rather than counts. They are good for seeing if there is an association between two variables

Try It!
Asha asked 82 classmates whether they play sports on the weekend. The results are shown in the two-way frequency table below.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 60.1

Convince Me!
How is a two-way relative frequency table different from a two-way frequency table?
Answer:
When a two-way table displays percentages or ratios (called relative frequencies), instead of just frequency counts, the table is referred to as a two-way relative frequency table. These two-way tables can show relative frequencies for the whole table, for rows, or for columns.

Use Asha’s two-way frequency table to complete the two-way relative frequency table.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 60.2
Answer:
The given two-way table is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 60.1
Now,
We know that,
The % of boys or girls who say yes = \(\frac{The number of boys or girls who say yes}{The total number of people}\) × 100
The % of boys or girls who say no = \(\frac{The number of boys or girls who say no}{The total number of people}\) × 100
From the given two-way frequency table,
The total number of people is: 82
Hence,
The complete two-way relative frequency table for the given situation is:

Try It!
Use the data in the table below.

a. How does the percent of students who choose e-books compare to the percent of students who choose audiobooks?
Answer:
From the given two-way relative frequency table,
We can observe that
The % of students who choose e-books is: 52%
The % of students who choose Audiobooks is: 48%
So,
The % of students who choose e-books to the % of students who choose audiobooks
= \(\frac{48}{52}\) × 100
= 92.3%
Hence, from the above,
We can conclude that the % of students who choose e-books to the % of students who choose audiobooks is: 92.3%

b. Is there evidence that 7th graders have a greater tendency to choose audiobooks? Explain.
Answer:
From the given two-way relative frequency table,
The % of 7th-grade students who choose audiobooks is: 58.9%
The % of the 6th-grade students who choose audiobooks is: 36.5%
So,
The % of 7th-grade students who choose audiobooks > The % of 6th-grade students who choose audiobooks
Hence, from the above,
We can conclude that there is a piece of evidence that 7th-graders have a greater tendency to choose audiobooks

KEY CONCEPT
Relative frequency is the ratio of a data value to the total of a row, a column, or the entire data set. It is expressed as a percent. A total two-way relative frequency table gives the percent of the population that is in each group.
In a row two-way relative frequency table, the percents in each row add up to 100%.
In a column two-way relative frequency table, the percents in each column add up to 100%.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 60.3

Do You Understand?

Question 1.
? Essential Question
What is the advantage of a two-way relative frequency table for showing relationships between sets of paired data?
Answer:
Two-way relative frequency tables show us percentages rather than counts. They are good for seeing if there is an association between two variables

Question 2.
Reasoning when comparing relative frequency by rows or columns only, why do the percentages not total 100%? Explain.
Answer:
When comparing relative frequency by rows or columns only, the individual percentages will not be 100%
So, their total will also not be equal to 100%

Question 3.
Critique Reasoning
Maryann says that if 100 people are surveyed, the frequency table will provide the same information as a total relative frequency table. Do you agree? Explain why or why not.
Answer:
It is given that
Maryann says that if 100 people are surveyed, the frequency table will provide the same information as a total relative frequency table
We know that,
The “Two-way frequency table” gives us information about the categories in the form of counts and frequencies
The “Two-way relative frequency table” gives us information about the categories in terms of percentages of frequencies
Hence, from the above,
We can agree with Maryann

Do You Know How?

In 4-6, use the table. Round to the nearest percent.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 70.1

Question 4.
What percent of the people surveyed have the artistic ability?
Answer:
From the table,
The number of people who have the artistic ability is: 101
Now,
We know that,
The % of the people surveyed that have the artistic ability = \(\frac{The total number of people who have the artistic ability}{The total number of people}\) × 100
= \(\frac{101}{223}\) × 100
= 45%
Hence, from the above,
We can conclude that 45% of the people surveyed have the artistic ability

Question 5.
What percent of left-handed people surveyed have the artistic ability?
Answer:
From the table,
The number of left-handed people who have artistic ability is: 86
Now,
We know that,
The % of the left-handed people surveyed that have the artistic ability = \(\frac{The total number of left-handed people who have the artistic ability}{The total number of people}\) × 100
= \(\frac{86}{223}\) × 100
= 39%
Hence, from the above,
We can conclude that 39% of the left-handed people surveyed have the artistic ability

Question 6.
What percent of the people who have the artistic ability are left-handed?
Answer:
From the table,
The number of left-handed people who have artistic ability is: 86
Now,
We know that,
The % of the left-handed people surveyed that have the artistic ability = \(\frac{The total number of left-handed people who have the artistic ability}{The total number of people}\) × 100
= \(\frac{86}{223}\) × 100
= 39%
Hence, from the above,
We can conclude that 39% of the left-handed people surveyed have the artistic ability

Practice & Problem Solving

Leveled Practice in 7-8, complete the two-way relative frequency tables.

Question 7.
In a group of 120 people, each person has a dog, a cat, or a bird. The two-way frequency table shows how many people have each kind of pet. Complete the two-way relative frequency table to show the distribution of the data with respect to all 120 people. Round to the nearest tenth of a percent.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.1
Answer:
It is given that
In a group of 120 people, each person has a dog, a cat, or a bird. The two-way frequency table shows how many people have each kind of pet
Hence,
The complete two-way relative frequency table for the given situation is:

Question 8.
There are 55 vehicles in a parking lot. The two-way frequency table shows data about the types and colors of the vehicles. Complete the two-way relative frequency table to show the distribution of the data with respect to color. Round to the nearest tenth of a percent.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.2
Answer:
It is given that
There are 55 vehicles in a parking lot. The two-way frequency table shows data about the types and colors of the vehicles.
Hence,
The completed two-way relative frequency table that shows the distribution of the data with respect to color is:

Question 9.
Men and women are asked what type of car they own. The table shows the relative frequencies with respect to the total population asked. Which type of car is more popular?
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.5
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.6
Answer:
It is given that
Men and women are asked what type of car they own. The table shows the relative frequencies with respect to the total population asked.
Now,
The given two-way relative frequency table is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.6
Now,
From the given table,
We can observe that
Most of the people have shown interest in the 4-door type of car
Hence, from the above,
We can conclude that the 4-door type of car is more popular

Question 10.
Make Sense and Persevere Students were asked if they like raspberries. The two-way relative frequency table shows the relative frequencies with respect to the response.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.7
a. What percent of students who do not like raspberries are girls?
Answer:
It is given that
Students were asked if they like raspberries. The two-way relative frequency table shows the relative frequencies with respect to the response.
Now,
From the given two-way frequency table,
We can observe that the % of girls who do not like raspberries are: 48%
Hence, from the above,
We can conclude that the % of students who do not like raspberries are girls is: 48%

b. Is there evidence of an association between the response and the gender? Explain.
Answer:
From the given two-way relative frequency table,
We can observe that
The % of girls who like raspberries is more than the % of boys who like raspberries
The % of girls who do not like raspberries is less than the % of boys who do not like raspberries

Question 11.
Higher-Order Thinking All the workers in a company were asked a survey question. The two-way frequency table shows the responses from the workers in the day shift and night shift.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.8
a. Construct a two-way relative frequency table to show the relative frequencies with respect to the shift.
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.9
Answer:
It is given that
All the workers in a company were asked a survey question. The two-way frequency table shows the responses from the workers in the day shift and night shift.
Now,
The given two-way frequency table is:
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.8
Hence,
The completed two-way relative frequency table for the survey is:

b. Is there evidence of an association between the response and the shift? Explain.
Answer:
From the two-way frequency table that is mentioned in part (a),
We can observe that
The % of people who opted for the day shift are more than the % of people who opted for the night shift

Assessment Practice

Question 12.
Patients in a blind study were given either Medicine A or Medicine B. The table shows the relative frequencies
Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 80.11
Is there evidence that improvement was related to the type of medicine? Explain.
A. The same number of people took each medicine, but the percent of people who reported improvement after taking Medicine B was significantly greater than the percent for Medicine A.
B. The same number of people took each medicine, but the percent of people who reported
improvement after taking Medicine A was significantly greater than the percent for Medicine B.
C. Different numbers of people took each medicine, but the percent of people who reported improvement after taking Medicine B was significantly greater than the percent for Medicine A.
D. Different numbers of people took each medicine, but the percent of people who reported improvement after taking Medicine A was significantly greater than the percent for Medicine B.
Answer:
It is given that
Patients in a blind study were given either Medicine A or Medicine B. The table shows the relative frequencies
We know that,
The number of people will be different
Now,
When we observe the given two-way related frequency table,
The improvement due to Medicine B > The improvement due to Medicine A
Hence, from the above,
We can conclude that option C matches the given situation

3-Act Mathematical Modeling: Reach Out

3-ACT MATH

Envision Math Common Core Grade 8 Answers Topic 4 Investigate Bivariate Data 100

ACT 1

Question 1.
After watching the video, what is the first question that comes to mind?
Answer:

Question 2.
Write the Main Question you will answer.
Answer:

Question 3.
Construct Arguments Predict an answer to this Main Question. Explain your prediction.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 90.1
Answer:

Question 4.
On the number line below, write a number that is too small to be the answer. Write a number that is too large.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 90.2
Answer:

Question 5.
Plot your prediction on the same number line.
Answer:

ACT 2

Question 6.
What information in this situation would be helpful to know? How would you use that information?
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 90.3
Answer:

Question 7.
Use Appropriate Tools What tools can you use to solve the problem? Explain how you would use them strategically.
Answer:

Question 8.
Model with Math
Represent the situation using mathematics. Use your representation to answer the Main Question.
Answer:

Question 9.
What is your answer to the Main Question? Is it higher or lower than your initial prediction? Explain why.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 91.2
Answer:

ACT 3

Question 10.
Write the answer you saw in the video.
Answer:

Question 11.
Reasoning Does your answer match the answer in the video? If not, what are some reasons that would explain the difference?
Answer:

Question 12.
Make Sense and Persevere Would you change your model now that you know the answer? Explain.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 92.1
Answer:

Reflect

Question 13.
Model with Math
Explain how you used a mathematical model to represent the situation. How did the model help you answer the Main Question?
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 93.1
Answer:

Question 14.
Critique Reasoning Choose a classmate’s model. How would you adjust that model?
Answer:

SEQUEL

Question 15.
Model with Math Measure a classmate’s wingspan. Use your model to predict your classmate’s height. How well did your model predicts your classmate’s actual height?
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 94.1
Answer:

Topic 4 REVIEW

? Topic Essential Question

How can you represent the relationship between paired data and use the representation to make predictions?
Answer:
The scatter diagram graphs pairs of numerical data, with one variable on each axis, to look for a relationship between them. If the variables are correlated, the points will fall along a line or curve. The better the correlation, the tighter the points will hug the line

Vocabulary Review

Match each example on the left with the correct word and then provide another example.

Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 94.5

Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 94.6
Answer:

Use Vocabulary in Writing
Describe the scatter plot at the right. Use vocabulary terms in your description.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 94.7
Answer:
The given scatter plot is:
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 94.7
Now,
From the given scatter plot,
We can observe that
With the help of measurement data, a trend line is drawn
There is a trend line that is not passing through the origin
There is an outlier present in the given scatter plot

Concepts and Skills Review

LESSON 4.1 Construct and Interpret Scatter Plots

Quick Review
A scatter plot shows the relationship between paired measurement data. Scatter plots can be used to interpret data by looking for clusters, gaps, and outliers.

Practice
The table shows the distance in miles and the price of airfare in dollars.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 94.8

Question 1.
Construct a scatter plot.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 95.1
Answer:
It is given that
The table shows the distance in miles and the price of airfare in dollars.
Hence,
The representation of the scatter plot that describes the relationship between the price of airfare and distance is:

Question 2.
Is there a relationship between distance and airfare? Explain.
Answer:
From the above scatter plot,
We can observe that there is no association between distance and airfare
Hence, from the above,
We can conclude that there is no relationship between distance and airfare

LESSON 4.2 Analyze Linear Associations

Quick Review
The association between the data in a scatter plot can be linear or nonlinear. A trend line is a line on a scatter plot, drawn near the points, which approximates the association between paired data. If the data are linear, the association can be positive or negative, and strong or weak.

Practice
Identify the association between the data on each scatter plot.

Question 1.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 96.1
Answer:
The given scatter plot is:
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 96.1
Now,
From the given scatter plot,
We can observe that as the value of x increases, the value of y decreases
Hence, from the above,
We can conclude that there is a negative association between the data in the scatter plot

Question 2.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 96.2
Answer:
The given scatter plot is:
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 96.2
From the given scatter plot,
We can observe that the data is in a non-linear trend
Hence, from the above,
We can conclude that there is a non-linear association between the data in the scatter plot

LESSON 4.3 Use Linear Models to Make Predictions

Quick Review
To make predictions, substitute known values into the equation of a linear model to solve for an unknown.

Practice
The scatter plot shows the wages of employees.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 96.11

Question 1.
If an employee earns $570, what is the expected number of copies sold?
Answer:
It is given that
The scatter plot shows the wages of employees.
Now,
The given scatter plot is:
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 96.11
From the given scatter plot,
We can observe that
The equation of the trend line is:
y = 6x + 120
Where,
y is the wages
x is the number of copies sold
Now,
For y = $570,
570 = 6x + 120
6x = 570 – 120
6x = 450
x = \(\frac{450}{6}\)
x = 75
Hence, from the above,
We can conclude that for an employee wage of $570, the number of copies sold is: 75

Question 2.
If an employee sells 100 copies, what is the expected wage?
Answer:
For x = 100,
y = 6x + 120
y = 6 (100) + 120
y = 600 + 120
y = 720
Hence,f rom the above,
We can conclude that
If an employee sells 100 copies, then the expected wage is: $720

LESSON 4.4 Interpret Two-Way Frequency Tables

Quick Review
A two-way frequency table displays the relationship between paired categorical data.

Practice

Question 1.
The two-way frequency table shows the results of a random survey of movies watched by 100 students. Mrs. Leary said that according to the data, girls are more likely than boys to watch movie A. Is the statement true or false? Explain.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 97.1
Answer:
It is given that
The two-way frequency table shows the results of a random survey of movies watched by 100 students.
Now,
The given statement is:
Mrs. Leary said that according to the data, girls are more likely than boys to watch movie A.
Now,
The given two-way frequency table is:
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 97.1
Now,
From the given two-way frequency table,
We can observe that
The number of girls who watch movie A > The number of boys who watch movie A
Hence, from the above,
We can conclude that the given statement is true

LESSON 4.5 Interpret Two-Way Relative Frequency Tables

Quick Review
Relative frequency is the ratio of a data value to the total of a row, a column, or the entire data set. It is expressed as a percent.

Practice

The two-way table shows the eye color of 200 cats participating in a cat show.
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 98.1

Question 1.
Make a two-way relative frequency table to show the distribution of the data with respect to gender. Round to the nearest tenth of a percent, as needed.
Answer:
It is given that
The two-way table shows the eye color of 200 cats participating in a cat show.
Now,
The given two-way frequency table is:
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 98.1
Hence,
The representation of the two-way relative frequency table that shows the distribution of the data wrt gender is:

Question 2.
What percent of cats that are female have blue eyes?
Answer:
From the above two-way relative frequency table,
We can observe that there are 30% of cats that are females who have blue eyes
Hence, from the above,
We can conclude that the percent of cats that are females and have blue eyes is: 30%

Topic 4 Fluency Practice

Hidden Clue
For each ordered pair, solve the equation to find the unknown coordinate. Then locate and label the corresponding point on the graph. Draw line segments to connect the points in alphabetical order. Use the completed picture to help you answer the riddle below.

Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.1
Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.2

A (6, -0.5y + 20 – 0.5y = 13). 6, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

B (4 – 3x – 7x = -8, 7) Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6, 7

C (2x + 4 – 6x = 24, 5) Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6, 5

D (5x + 6 – 10x = 31, 1) Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6, 1

E (7x – 3 – 3x = 13, -2) Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6, -2

F (4, -12y + 8y – 21 = -5) 4, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

G (44 = 6x – 1 + 9x, –5) 4, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6, -5

H(-5, 4y + 14 – 2y = 4) -5, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

I (-5, 15+ y + 6 + 2y = 0) -5, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

J (4, 3y + 32 – y = 18) 4, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

K (6, 5y + 20 + 3y = -20) 6, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

L (9x – 14 – 8x = -8, -1) Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6, -1

M(-3, -5y + 10 – y = -2) -3, Envision Math Common Core 8th Grade Answer Key Topic 4 Investigate Bivariate Data 99.6

N(-13 + x – 5 – 4x = -9, 4)
Answer:
The solutions of the above equations are:

Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction

Envision Math 5th Grade Textbook Answer Key Topic 19.8 Writing Probability as a Fraction

Writing Probability as a Fraction

What is the probability of an event?
Answer:
Reuben writes each letter of his name on a separate piece of paper and puts them in a bag. He chooses one piece of paper from the bag without looking.
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 1
The probability of an event is a number that describes the chance the event will occur.

Another Example
What is the probability of two events happening together?
Answer:
Eva puts the letters of her name into a bag and chooses a letter out of the bag without looking. She puts the letter back into the bag and chooses again without looking. What is the probability that Eva chooses an A both times?
Draw a tree diagram.
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 2

Find the probability.
Answer:
There are a total of 9 possible outcomes when the two letters are chosen and the first is replaced. One of the outcomes is favorable because only one of the outcomes has an A both times.
The probabilty of any event ranges from 0 to 1.
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 3
P(A, A) = \(\frac{1}{9}\)
The probability that Eva chooses an A both times is \(\frac{1}{9}\) .

Explain It
Question 1.
Use the tree diagram above to find the probability of choosing the same letter twice. Hint: Look for pairs of outcomes with the same letter.
Answer:

Question 2.
If an event has a probability of \(\frac{3}{4}\), is it less likely, more likely, equally likely, impossible, or certain to occur?
Answer:

Probability of an event = \(\frac{\text { number of favorable outcomes }}{\text { total number of possible outcomes }}\)

What is the probability that Reuben will choose the letter B?
There is 1 favorable outcome out of 6 possible outcomes, R, E, U, B, E, or N. The outcomes are equally likely (have the same chance of occurring). The probability of choosing the letter B can be written as P(B).
P(B) = \(\frac{1}{6}\)
The probability that Reuben chooses a B out of the bag is \(\frac{1}{6}\).

What is the probability that Reuben will choose the letter E?
There are 2 favorable outcomes out of 6 possible outcomes (since E appears twice).
P(E) = \(\frac{2}{6}\) = \(\frac{1}{3}\)
The probability that Reuben chooses an E out of the bag is \(\frac{1}{3}\) or P(E) = \(\frac{1}{3}\).

Guided Practice

Do you know HOW?
For 1 through 4, use the spinner shown
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 4
Question 1.
Find P(blue).
Answer:

Question 2.
Find P(yellow).
Answer:

Question 3.
Find P(red).
Answer:

Question 4.
Find P(green).
Answer:

Do you UNDERSTAND?
Question 5.
Writing to Explain
In the example above, is it likely, unlikely, impossible, or certain that Reuben draws a B?
Answer:

Question 6.
What is the probability that Reuben will NOT draw an R?
Answer:

Independent Practice

Question 7.
Write each letter of your first name on a separate small sheet of paper. Put each piece into a box. Do an experiment where you pick one letter and replace it each time. Do this 10 times. Record the number of times you pick each letter, and then write the probability as a fraction.
Answer:

For 8 through 12, suppose you toss a quarter and a penny.
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 5
Question 8.
Make a tree diagram to show the possible outcomes.
Answer:

Question 9.
Find P(one head).
Answer:

Question 10.
Find P(two heads).
Answer:

Question 11.
Find P(quarter heads, penny tails)
Answer:

Question 12.
Find P(no heads)
Answer:

Question 13.
When a number cube is tossed, there are 6 possible outcomes (1,2, 3, 4, 5, or 6). If the cube is tossed twice and the outcomes are added, the possible sums are from 2 through 12.
Answer:

Copy the table and give the probability of each sum.
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 6
Question 14.
Which sum (or sums) has the greatest probability of occurring?
Answer:

Question 15.
Which sum (or sums) has the least probability of occurring?
Answer:

Problem Solving

Question 16.
Geometry
Kendra tosses a colored cube. Half of the sides of the cube are red, \(\frac{1}{3}\) of the sides are blue, and one side is green. What is the probability that the cube will land on a color other than red when tossed?
Answer:

Question 17.
Mrs. Pierre bought 150 pencils to give to her students. She has three classes with 27, 25, and 23 students each. She wants every student to get the same number of pencils. How many pencils should she give to each student?
Answer:

Question 18.
Think About the Process
Jorge put colored cards into a bag. Two of the cards were green, three were red, one was orange, two were blue, and two were purple. Jorge wants to find the probability that he will pull an orange card from the bag. What step does Jorge take to determine the number of possible outcomes?
A. Count the number of orange cards.
B. Count the number of different colored cards.
C. Count the total number of cards in the bag.
D. Count the number of cards that are not orange.
Answer:

Question 19.
Carlita buys 3 beanbag throws for $1.00. What is the probability she will toss one beanbag through a hole in the top row of this game? Assume Carlita always throws a beanbag into a hole.
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 7
Answer:

Question 20.
How many parts of each color should there be to make sure that it is equally likely this spinner will land on each of 3 different colors?
Envision Math Grade 5 Answer Key Topic 19.8 Writing Probability as a Fraction 8
Answer:

Algebra Connection

Which Equation is True?
Answer:
Remember that an equation is a number sentence that uses an equal sign to show that two expressions are equal. Both of the following are equations.
8 + 2 = 10
x + 25 = 100
The first equation is true. You don’t know if an algebraic equation is true or false until you replace the variable with a number.
If x = 75, then x + 25 = 100 is a true equation.

Example:
If m = 25, which equation is true?
2 + m = 30
m – 20 = 5
In the first equation, if you replace m with 25, the result is 2 + 25 = 30. This equation is false.
In the second equation if you replace m with 25, the result is 25 – 20 = 5. This equation is true.

Decide which equation is true for each replacement of the variable.
Question 1.
If x = 20, which equation is true?
Answer:

Question 2.
If y = 100, which equation is true? y – 80 = 180 or y ÷ 2 = 50
Answer:

Question 3.
If x = 50, which equation is true? x + 50 = 75 or \(\frac{x}{10}\) = 5
Answer:

Question 4.
If x = 80, which equation is true? 40x = 3,200 or \(\frac{x}{4}\) = 2
Answer:

Question 5.
If z = 200, which equation is true? 200 – x = 200 or x + 100 = 300
Answer:

Question 6.
If x = 70, which equation is true? 6x = 420 or x + 7 = 63
Answer:

Question 7.
If x = 0, which equation is true? 50x = 50 x + 7 = 7
Answer:

Question 8.
If x = 1, which equation is true? 40x = 40 or 40 + x = 40
Answer:

Question 9.
If a teacher has 32 students and divides them into teams of 4, which equation could be used to find how many students will be on each team? Let x represent the number of students on each team.
\(\frac{32}{4}\) = x
4 + x = 32
\(\frac{32}{x}\) = 4
4 × 32 = x
Answer:

Envision Math Grade 5 Answer Key Topic 19.7 Outcomes

Envision Math 5th Grade Textbook Answer Key Topic 19.7 Outcomes

Outcomes

How can tree diagrams help you list possible outcomes?
How many outcomes are possible when spinning a spinner once and then tossing a coin twice?
Envision Math 5th Grade Answer Key Topic 19.7 Outcomes 1
Answer:

Question.
Use a tree diagram to list all possible outcomes.
Answer:
A tree diagram is a diagram used to organize outcomes of an experiment.

Guided Practice

Do you know HOW?
In 1 through 3, list the possible outcomes.
Question 1.
Tossing a number cube
Answer:

Question 2.
Spinning a spinner divided into white, blue, black, and purple
Answer:

Question 3.
Tossing an even number on a number cube
Answer:

Do you UNDERSTAND?
Question 4.
Writing to Explain
In the example above, how would your tree diagram change if the spinner had 4 colors? How many possible outcomes would there be?
Answer:

Question 5.
Write a multiplication equation to find the possible outcomes of tossing a number cube and spinning a spinner with 4 different colors.
Answer:

Independent Practice

Question 6.
Two spinners are spun. Copy and complete the tree diagram to show the possible outcomes.
Envision Math 5th Grade Answer Key Topic 19.7 Outcomes 2
Answer:

Question 7.
Josh and Susan are running for class president. Mark, Maria, Lee, and Eva are running for vice-president. How many possible outcomes are there for electing a president and a vice president?
Answer:

A tree diagram shows the sample space, which is the set of all possible outcomes.
Envision Math 5th Grade Answer Key Topic 19.7 Outcomes 3

You can also find the number of outcomes by multiplying.
Envision Math 5th Grade Answer Key Topic 19.7 Outcomes 4
There are 8 possible outcomes.

Problem Solving

Question 8.
On four tests, Justin scored 90, 85, 90, and 95. What is the mean score of the four tests?
Answer:

Question 9.
Steve’s dog is 10 lb heavier than Marsha’s dog. Together, the dogs weigh 42 lb. How much does each dog weigh?
Answer:

Question 10.
John, Andy, and Miguel run in the first race. Sharon, Marie, and Mona run in the second race. How many different outcomes are possible for the winning pairs?
A. 3
B. 6
C. 9
D. 12
Answer:

Question 11.
Surfers in California often have a variety of wetsuits and surfboards. If a surfer has 3 wetsuits and 6 surfboards, how many different combinations of a wetsuit and a surfboard could the surfer have?
A. 6
B. 9
C. 18
D. 36
Answer:

Question 12.
Writing to Explain
How does a tree diagram make it easier to tell which outcome occurs most often?
Answer:

Question 13.
Lara’s ice skating lesson started at 11:15 A.M. and ended at 12:50 P.M. How long did the lesson last?
Answer:

Question 14.
Think About the Process
Jennifer’s paycheck was $314.79. She used $205.75 of that money to pay bills. Then she spent $58 on groceries. Which expression shows how to find how much money Jennifer has left?
A. $314.79 + $205.75 – $58
B. $314.79 – $205.75 – $58
C. $314.79 – $205.75 + $58
D. $314.79 + $205.75 + $58
Answer:

Question 15.
How many different outfits consisting of one pair of jeans, one T-shirt, and one jacket can you make if you have three pairs of jeans, four T-shirts, and two jackets to choose from?
Answer:

Question 16.
Algebra Find the value of n, if n × 400 = 28,000.
Answer:

Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations

enVision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations

Go through the enVision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations regularly and improve your accuracy in solving questions.

enVision Math Common Core 8th Grade Answers Key Topic 2 Analyze And Solve Linear Equations

Topic Essential Question
How can we analyze connections between linear equations, and use them to solve problems?
Answer:
One of the more obvious “connections” between linear equations is the presence of the same two variables (Generally, in most cases x and y) in these equations.
Assuming that your two equations are distinct (neither is merely a multiple of the other), we can use the “elimination by addition and subtraction” method or “Substitution method” to eliminate one variable, leaving us with an equation in one variable,
solve this 1-variable (x) equation, and then use the resulting value in the other equation to find the value of the other variable (y).
By doing this we find a unique solution (x, y) that satisfies both original equations.
Not only that but also this solution (x, y) will also satisfy both of the original linear equations.

3-ACT MATH
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 1

Powering Down
Do you know that feeling when you realize you left your charger at home? Uh-oh. It’s only a matter of time before your device runs out of power. Your battery percentage is dropping, but you still have so much left to do. Think about this during the 3-Act Mathematical Modeling lesson.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 2

Topic 2 enVision STEM Project

Did You Know?
Demography is the study of changes, such as the number of births, deaths, or net migration, occurring in the human population over time.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 3

Deaths Worldwide in 2015 (estimated)
Emigration is the act of leaving one’s country to settle elsewhere. In 2015, 244 million people, or 3.3% of the world’s population, lived outside their country of origin.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 4
Immigration is the act of entering and settling in a foreign country. The United States has the largest immigrant population in the world.

Your Task: Modeling Population Growth
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 5
Human population numbers are in constant flux. Suppose a country has a population of 20 million people at the start of one year and during the year there are 600,000 births, 350,000 deaths, 100,000 immigrants, and 5,000 emigrants. You and your classmates will determine the total population at the end of the year and then model the expected change over a longer period.
Answer:
It is given that the population at the start of the year is 20 million people and during that year, there are 600,000 births, 350,000 deaths, 100,000 immigrants, and 5,000 emigrants
So,
The total population at the end of the year = (Total population at the start of the year) – ( Births + Deaths + Immigrants + Emigrants at that year)
= 20 million – (600,000 + 350,000 + 100,000 + 5,000)
= 20 million – 10.5 million
= 9.5 million
Change in Population = (Births + Immigration) – (Deaths + Emigration)
= (600,000 + 100,000) – (350,000 + 5,000)
= 700,000 – 355,000
= 345,000
Hence, from the above,
We can conclude that
The total population at the end of the year is: 9.5 million
The change in population at that year is: 345,000

Analyze And Solve Linear Equations 1

Topic 2 GET READY!

Review What You Know!

Vocabulary
Choose the best term from the box to complete each definition.
inverse operations
like terms
proportion
variables

Question 1.
In an algebraic expression, __________ are terms that have the same variables raised to the same exponents.
Answer:
We know that,
In an algebraic expression, “Like terms” are terms that have the same variables raised to the same exponents.
Hence, from the above,
We can conclude that the best term that fits the given definition is: Like terms

Question 2.
Quantities that represent an unknown value are _________.
Answer:
We know that,
Quantities that represent an unknown value are “Variables”
Hence, from the above,
We can conclude that the best term that fits the given definition is: Variables

Question 3.
A _________ is a statement that two ratios are equal.
Answer:
We know that,
A “Proportion” is a statement that two ratios are equal.
Hence, from the above,
We can conclude that the best term that fits the given definition is: Proportion

Analyze And Solve Linear Equations 2

Question 4.
Operations that “undo” each other are __________.
Answer:
We know that,
Operations that “undo” each other are ” Inverse Operations”
Hence, from the above,
We can conclude that the best term that fits the given definition is: Inverse Operations

Identify Like Terms

Complete the statements to identify the like terms in each expression.
Question 5.
4x + 7y – 62 + 6y – 9x
4x and ______ are like terms.
7y and _______ are like terms.
Answer:
The given expression is:
4x + 7y – 62 + 6y – 9x
We know that,
The “Like terms” are terms that have the same variables raised to the same exponents.
Hence, from the above,
We can conclude that
4x and 9x are like terms
7y and 6y are like terms

Question 6.
\(\frac{1}{2}\)s – (6u – 9u) + \(\frac{1}{10}\)s + 25
\(\frac{1}{2}\)s and _______ are like terms.
6u and _______ are like terms.
Answer:
The given expression is:
\(\frac{1}{2}\)s – (6u – 9u) + \(\frac{1}{10}\)s + 25
= \(\frac{1}{2}\)s + 9u – 6u + \(\frac{1}{10}\)s + 25
We know that,
The “Like terms” are terms that have the same variables raised to the same exponents.
Hence, from the above,
We can conclude that
\(\frac{1}{2}\)s and \(\frac{1}{10}\)s are like terms
6u and 9u are like terms

Solve One-Step Equations

Simplify each equation.
Question 7.
2x = 10
Answer:
The given expression is:
2x = 10
Divide by 2 into both sides
\(\frac{2}{2}\)x = \(\frac{10}{2}\)
x = 5
Hence, from the above,
We can conclude that the value of x is: 5

Question 8.
x + 3 = 12
Answer:
The given expression is:
x + 3 = 12
Subtract with 3 on both sides
x + 3 – 3 = 12 – 3
x = 9
Hence, from the above,
We can conclude that the vaue of x is: 9

Question 9.
x – 7 = 1
Answer:
The given expression is:
x – 7 = 1
Add with 7 on both sides
x – 7 + 7 = 1 + 7
x = 8
Hence, from the above,
We can conclude that the value of x is: 8

Simplify Fractions

Question 10.
Explain how to simplify the fraction \(\frac{12}{36}\).
Answer:
The given fraction is:
\(\frac{12}{36}\)
From the given fraction,
We can observe that the numerator and the denominator are the multiples of 12
So,
Divide the numerator by 12 and the denominator by 12
So,
\(\frac{12}{36}\) = \(\frac{1}{3}\)
Hence,
The simplified form of the given fraction is: \(\frac{1}{3}\)

Language Development
Fill in the Venn diagram to compare and contrast linear equations of the form y = mx and y = x + b.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 6

In the box below, draw graphs to represent each form of the linear equations.

Topic 2 PICK A PROJECT

PROJECT 2A
If you had to escape from a locked room, how would you start?
PROJECT: DESIGN AN ESCAPE-ROOM ADVENTURE
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 7

PROJECT 2B
What animal would you most like to play with for an hour? Why?
PROJECT: PLAN A PET CAFÉ
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 8

PROJECT 2C
If you wrote a play, what would it be about?
PROJECT: WRITE A PLAY
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 9

PROJECT 2D
How many tiny steps does it take to cross a slackline?
PROJECT: GRAPH A WALKING PATTERN
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 10

Lesson 2.1 Combine Like Terms to solve Equations

Explore It!
A superintendent orders the new laptops shown below for two schools in her district. She receives a bill for $7,500.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 11
I can… solve equations that have like terms on one side.

A. Draw a representation to show the relationship between the number of laptops and the total cost.
Answer:
It is given that she receives a bill for $7,500
So,
The total cost of the laptops that are given in the above figure = $7,500
Now,
Let the cost of a laptop be $x
So,
$3x + $4x + $3x = $7,500
$10x = $7,500
Hence, from the above,
We can conclude that
The representation to show the relationship between the number of laptops and the total cost is:
$10x = $7,500

B. Use the representation to write an equation that can be used to determine the cost of one laptop.
Answer:
From part (a),
The representation to show the relationship between the number of laptops and the total cost is:
$10x = $7,500
Divide with 10 into both sides
So,
\(\frac{$10x}{10}\) = \(\frac{$7,500}{10}\)
$x = $750
Hence, from the above,
We can conclude that
The representation to write an equation that can be used to determine the cost of one laptop is:
$x = $750

Analyze And Solve Linear Equations 3

Focus on math practices
Reasoning Why is it important to know that each laptop costs the same amount?
Answer:
From the given figure,
We can observe that all the laptops are of the same type
So,
Each laptop will cost the same amount since all the laptops are the same

Essential Question
How do you solve equations that contain like terms?
Answer:
We will solve the equations that contain like terms by rearranging the like terms on either the left side or the right side

Try It!

Selena spends $53.94 to buy a necklace and bracelet set for each of her friends. Each necklace costs $9.99, and each bracelet costs $7.99. How many necklace and bracelet sets, s, did Selena buy?
Selena buys necklace and bracelet sets for _________ friends.
_____ s + ______ s = 53.94
______ s = 53.94
s = ______
Answer:
Let each necklace and each bracelet be s
It is given that
The cost of each necklace is: $9.99
The cost of each bracelet is: $7.99
The total cost of a necklace and a bracelet is: $53.94
So,
$9.99s + $7.99s = $53.94
$17.98s = $53.94
$1798s = $5394
Divide by 1798 on both sides
\(\frac{$1798}{1798}\)s = \(\frac{$5394}{1798}\)
s = 3
Hence, from the above,
We can conclude that the number of necklace and bracelet sets that Selena buy is: 3

Convince Me!
Suppose the equation is 9.99s + 7.99s + 4.6 = 53.94. Can you combine the s terms and 4.6? Explain.
Answer:
The given equation is:
9.99s + 7.99s + 4.6 = 53.94
We know that,
We can only combine the terms only when they are the “Like terms”
So,
In the given equation,
9.99s and 7.99s are the like terms
53.94 and 4.6 are the like terms
Hence, from the above,
We can conclude that we can not combine the s terms and 4.6

Analyze And Solve Linear Equations 4

Try It!

Nat’s grocery bill was $150, which included a 5% club discount. What was Nat’s bill before the discount? Write and solve an equation.
Answer:
It is given that Nat’s grocery bill was $150 which included a 5% club discount
Now,
Let x be Nat’s bill before the discount
So,
To find Nat’s bill before discount, we have to find the value of 5% of 150 and add its value from 150
We know that,
The value of the bill will always be less after discount when compared to the value of the bill before discount
Now,
Nat’s bill before the discount = (Nat’s bill which included a 5% club discount) + (Value of 5% of 150)
x = $150 + (\(\frac{5}{100}\) × 150)
x = $150 + \(\frac{5 × 150}{100}\)
x = $150 + \(\frac{750}{100}\)
x = $150 + $7.5
x = $157.5
Hence, from the above,
We can conclude that Nat’s bill before the discount is: $157.5

Try It!

Solve for d.
a. –\(\frac{1}{4}\)d – \(\frac{2}{5}\)d = 39
Answer:
The given expression is:
–\(\frac{1}{4}\)d – \(\frac{2}{5}\)d = 39
-d (\(\frac{1}{4}\) + \(\frac{2}{5}\)) = 39
-d (0.25 + 0.40) = 39
-d (0.65) = 39
-d = \(\frac{39}{0.65}\)
-d = \(\frac{39 × 100}{65}\)
-d = 60
d = -60
Hence, from the above,
We can conclude that the value of d is: -60

b. -9.760 – (-12.81d) = 8.54
Answer:
The given expression is:
-9.760 – (-12.81d) = 8.54
-9.760 + 12.81d = 8.54
Rearrange the like terms in the above equation
So,
12.81d = 8.54 + 9.760
12.81d = 18.3
Divide by 12.81 on both sides
So,
\(\frac{12.81d}{12.81}\) = \(\frac{18.3}{12.81}\)
d = 1.428
Hence, from the above,
We can conclude that the value of d is: 1.428

KEY CONCEPT

In an equation with variable terms on one side, you can combine like terms before using inverse operations and properties of equality to solve the equation.
0.8n + 0.6n = 42
1.4n = 42 → Combine like terms.
\(\frac{1.4 n}{1.4}=\frac{42}{1.4}\)
n = 30

Do You Understand?
Question 1.
Essential Question How do you solve equations that contain like terms?
Answer:
In the equations that contain “Like terms”,
First, arrange the like terms at one side i.e., either the left side or the right side and combine them and then solve the equation for the desired result

Question 2.
Look for Relationships How do you recognize when an equation has like terms?
Answer:
We know that,
“Like terms” are terms that have the same variables raised to the same exponents.
Hence,
When there are the same variables in the given equation, we can call that terms “Like terms” in the given equation

Question 3.
Make Sense and Persevere in the equation 0.755 – \(\frac{5}{8}\)s = 44, how do you combine the like terms?
Answer:
The given equation is:
0.755 – \(\frac{5}{8}\)s = 44
We know that,
“Like terms” are terms that have the same variables raised to the same exponents.
So,
In the given equation,
0.755 and 44 are the like terms
So,
\(\frac{5}{8}\)s = 0.755 + 44
\(\frac{5}{8}\)s = 44.755
Multiply with \(\frac{8}{5}\) on both sides
So,
\(\frac{5}{8}\)s × \(\frac{8}{5}\) = 44.755 × \(\frac{8}{5}\)
s = 71.608
Hence, from the above,
We can conclude that the value of s is: 71.608

Do You Know How?
Question 4.
Henry is following the recipe card to make a cake. He has 95 cups of flour. How many cakes can Henry make?
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 12
Answer:
It is given that Henry is following the recipe card to make a cake and he has 95 cups of flour
It is also given that
We need
2\(\frac{2}{3}\) cups of flour for the batter
\(\frac{1}{2}\) cup of flour for the topping
Now,
Let the number of cakes be x
So,
By using the flour for the batter and the topping, Henry can make x cakes
Now,
(2\(\frac{2}{3}\) + \(\frac{1}{2}\))x = 95
We know that,
2\(\frac{2}{3}\) = \(\frac{8}{3}\)
So,
(\(\frac{8}{3}\) + \(\frac{1}{2}\))x = 95
\(\frac{19}{6}\)x = 95
Multiply with \(\frac{6}{19}\) on both sides
So,
\(\frac{19}{6}\)x × \(\frac{6}{19}\) = 95 × \(\frac{6}{19}\)
x = \(\frac{95 × 6}{19}\)
x = 30
Hence, from the above,
We can conclude that the number of cakes made by Henry is: 30

Question 5.
A city has a population of 350,000. The population has decreased by 30% in the past ten years. What was the population of the city ten years ago?
Answer:
It is given that a city has a population of 350,000 and it has decreased by 30% in the past ten years
Now,
Let the population of the city ten years ago be: x
To find the population of the city ten years ago,
We have to find the value of 30% of 350,000 and add it to the 350,000
The reason is it is given that the population i.e., 350,000 decreased in the past ten years. So, the population will be more than 350,000 ten years ago
So,
The population of the city ten years ago = (The population of the city in the past ten years) + (The value of 30% of 350,000)
x = 350,000 + \(\frac{30}{100}\) × 350,000
x = 350,000 + \(\frac{30 × 350,000}{100}\)
x = 350,000 + 105,000
x = 455,000
Hence, from the above,
We can conclude that the population of the city ten years ago is: 455,000

Question 6.
Solve the equation –12.2z – 13.4z = -179.2.
Answer:
The given equation is:
-12.2z – 13.4z = -179.2
From the given equation,
We can observe that 12.2 and 13.4 are the like terms
So,
-z(12.2 + 13.4) = -179.2
z(12.2 + 13.4) = 179.2
z(25.6) = 179.2
Divide by 25.6 into both sides
So,
\(\frac{25.6}{25.6}\)z = \(\frac{179.2}{25.6}\)
z = 7
Hence, from the above,
We can conclude that the value of z is: 7

Practice & Problem Solving

Leveled Practice In 7 and 8, complete the steps to solve for x.
Question 7.
\(\frac{4}{5}\)x – \(\frac{1}{4}\)x = 11
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 13
Answer:
The given equation is:
\(\frac{4}{5}\)x – \(\frac{1}{4}\)x = 11
x (\(\frac{4}{5}\) – \(\frac{1}{4}\)) = 11
x (\(\frac{16 – 5}{20}\)) = 11
\(\frac{11}{20}\)x = 11
Multiply with \(\frac{20}{11}\) on both sides
So,
\(\frac{20}{11}\) (\(\frac{11}{20}\)x) = 11 × \(\frac{20}{11}\)
x = \(\frac{11 × 20}{11}\)
x = 20
Hence, from the above,
We can conclude that the value of x is: 20

Question 8.
-0.65x + 0.45x = 5.4
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 14
Answer:
The given equation is:
-0.65x + 0.45x = 5.4
So,
x (0.45 – 0.65) = 5.4
x (-0.20) =5.4
Divide by -0.20 into both sides
So,
\(\frac{-0.20}{-0.20}\)x = \(\frac{5.4}{-0.20}\)
x = -27
Hence, from the above,
We can conclude that the avlue of x is: -27

In 9-12, solve for x.
Question 9.
\(\frac{4}{9}\)x + \(\frac{1}{5}\)x = 87
Answer:
The given equation is:
\(\frac{4}{9}\)x + \(\frac{1}{5}\)x = 87
So,
x (\(\frac{4}{9}\) + \(\frac{1}{5}\)) = 87
x (\(\frac{20 + 9}{45}\)) = 87
\(\frac{29}{45}\)x = 87
Multiply with \(\frac{45}{29}\) on both sides
So,
\(\frac{45}{29}\) (\(\frac{29}{45}\)x) = 87 × \(\frac{45}{29}\)
x = \(\frac{87 × 45}{29}\)
x = 135
Hence, from the above,
We can conclude that the value of x is: 135

Analyze And Solve Linear Equations 5

Question 10.
-3.8x – 5.9x = 223.1
Answer:
The given equation is:
-3.8x – 5.9x = 223.1
So,
-x (3.8 + 5.9) = 223.1
-x (9.7) =223.1
Divide by -9.7 into both sides
So,
\(\frac{-9.7}{-9.7}\)x = \(\frac{223.1}{-9.7}\)
x = -23
Hence, from the above,
We can conclude that the avlue of x is: -23

Question 11.
x + 0.15x = 3.45
Answer:
The givene quation is:
x + 0.15x = 3.45
So,
x (1 + 0.15) = 3.45
x (1.15) = 3.45
Divide be 1.15 into both sides
So,
\(\frac{1.15}{1.15}\)x = \(\frac{3.45}{1.15}\)
x = 3
Hence, from the above,
We can conclude that the value of x is: 3

Question 12.
–\(\frac{3}{5}\)x – \(\frac{7}{10}\) + \(\frac{1}{2}\)x = 56
Answer:
The given equation is:
–\(\frac{3}{5}\)x – \(\frac{7}{10}\) + \(\frac{1}{2}\)x = 56
x (\(\frac{1}{2}\) – \(\frac{3}{5}\)) – \(\frac{7}{10}\) = 56
x (\(\frac{5 – 6}{10}\)) – \(\frac{7}{10}\) = 56
–\(\frac{1}{10}\)x = 56 + \(\frac{7}{10}\)
–\(\frac{1}{10}\)x = \(\frac{560 + 7}{10}\)
Multiply with 10 on both sides
So,
–\(\frac{10}{10}\)x = \(\frac{567 × 10}{10}\)
-x = 567
x = -567
Hence, from the above,
We can conclude that the value of x is: -567

Question 13.
A contractor buys 8.2 square feet of sheet metal. She used 2.1 square feet so far and has $183 worth of sheet metal remaining. Write and solve an equation to find out how many sheets of metal costs per square foot.
Answer:
It is given that a contractor buys 8.2 square feet of sheet metal. She used 2.1 square feet so far and has $183 worth of sheet metal remaining.
So,
The remaining square feet of sheet metal = (Total square feet of sheet metal) – (The total square feet of sheet metal used so far)
The remaining square feet of sheet metal = 8.2 – 2.1
The remaining square feet of sheet metal = 6.1 square feet
Now,
It is given that there is$183 worth of sheet metal remaining
Now,
Let x be the number of sheet metals per square foot
So,
6.1x = $183
Divide by 6.1 into both sides
So,
\(\frac{6.1}{6.1}\)x = \(\frac{$183}{6.1}\)
x = 30
Hence, from the above,
We can conclude that the number of metal sheets per square foot is: 30

Question 14.
Make Sense and Persevere Clint prepares and sells trail mixes at his store. This week, he uses \(\frac{3}{8}\) his supply of raisins to make regular trail mix and \(\frac{1}{4}\) of his supply to make spicy trail mix. If Clint uses 20 pounds of raisins this week, how many pounds of raisins did he have at the beginning of the week?
Answer:
It is given that Clint prepares and sells trail mixes at his store and this week, he uses \(\frac{3}{8}\) his supply of raisins to make regular trail mix and \(\frac{1}{4}\) of his supply to make spicy trail mix.
So,
The total amount of raisins to make trail mix = (The supply of raisins to make regular mix) + (The supply of raisins to make spicy mix)
The total amount of raisins to make trail mix = \(\frac{3}{8}\) + \(\frac{1}{4}\)
The total amount of raisins to make trail mix = \(\frac{5}{8}\)
Now,
Let the number of pounds of raisins at the beginning of the week be x
So,
\(\frac{5}{8}\)x = 20
Multiply with \(\frac{8}{5}\) on both sides
So,
x = 20 × \(\frac{8}{5}\)
x = \(\frac{20 × 8}{5}\)
x = 32 pounds
Hence, from the above,
We can conclude that the number of pounds of raisins at the beginning of the week is: 32 pounds

Question 15.
Make Sense and Persevere A submarine descends to \(\frac{1}{6}\) of its maximum depth. Then it descends another \(\frac{2}{3}\) of its maximum depth. If it is now at 650 feet below sea level, what is its maximum depth?
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 15
Answer:
It is given that a submarine descends to \(\frac{1}{6}\) of its maximum depth and then it descends another \(\frac{2}{3}\) of its maximum depth and it is now at 650 feet below sea level
Now,
Let x be the maximum depth
So,
\(\frac{1}{6}\)x + \(\frac{2}{3}\)x = 650
\(\frac{1 + 4}{6}\)x = 650
\(\frac{5}{6}\)x = 650
Multiply with \(\frac{6}{5}\) on both sides
So,
x = 650 × \(\frac{6}{5}\)
x = \(\frac{650 × 6}{5}\)
x = 780 feet
Hence, from the above,
We can conclude that the maximum depth is: 780 feet

Question 16.
Model with Math Write an equation that can be represented by the bar diagram, then solve.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 16
Answer:
The given bar diagram is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 16
So,
From the bar diagram,
The representation of the equation is:
-1.2y + (-4.2y) = -3.78
-1.2y – 4.2y = -3.78
– (1.2y + 4.2y) = -3.78
1.2y + 4.2y = 3.78
5.4y = 3.78
Divide by 5.4 into both sides
So,
\(\frac{5.4}{5.4}\)y = \(\frac{3.78}{5.4}\)
y = 0.7
Hence, from the above,
We can conclude that the value of y is: 0.7

Question 17.
Higher Order Thinking Solve \(\frac{2}{3}\)h – 156 = 3\(\frac{13}{24}\).
Answer:
The given equation is:
\(\frac{2}{3}\)h – 156 = 3\(\frac{13}{24}\)
We know that,
3\(\frac{13}{24}\) = \(\frac{85}{24}\)
So,
\(\frac{2}{3}\)h – 156 = \(\frac{85}{24}\)
\(\frac{2}{3}\)h = \(\frac{85}{24}\) + 156
0.666h = 3.541 + 156
0.666h = 159.541
Divide by 0.666 into both sides
So,
h = \(\frac{159.541}{0.666}\)
h = 239.552
Hence, from the above,
We can conclude that the value of ‘h’ is: 239.552

Question 18.
Model with Math Nathan bought one notebook and one binder for each of his college classes. The total cost of the notebooks and binders was $27.08. Draw a bar diagram to represent the situation. How many classes is Nathan taking?
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 17
Answer:
It is given that Nathan bought one notebook and one binder for each of his college classes. The total cost of the notebooks and binders was $27.08.
Now,
Let the number of notebooks and binders that Nathan bought be x
From the figure,
It is given that
The cost of 1 notebook is: $0.95
The cost of 1 binder is: $5.82
So,
The representation of the cost of total notebooks and binders in the form of the equation is:
$0.95x + $5.82x = $27.08
Hence,
The representation of the above equation in the form of a bar diagram is:

Assessment Practice
Question 19.
Construct Arguments Your friend incorrectly says the solution to the equation –\(\frac{3}{5}\)y – \(\frac{1}{7}\)y = 910 is y = 676. What error did your friend make?
A. Added –\(\frac{1}{7}\) to –\(\frac{3}{5}\)
B. Subtracted \(\frac{1}{7}\) from –\(\frac{3}{5}\)
C. Multiplied 910 by \(\frac{26}{35}\)
D. Multiplied 910 by \(\frac{35}{26}\)
Answer:
The given equation is:
–\(\frac{3}{5}\)y – \(\frac{1}{7}\)y = 910
-y (\(\frac{3}{5}\) + \(\frac{1}{7}\)) = 910
–\(\frac{26}{35}\)y = 910
Multiply with –\(\frac{35}{26}\) on both sides
So,
y = -910 × \(\frac{35}{26}\)
y = -1,225
Hence from the above,
We can conclude that the error your friend makes is:
Multiplied 910 by \(\frac{26}{35}\)

Question 20.
A 132-inch board is cut into two pieces. One piece is three times the length of the other. Find the length of the shorter piece.
PART A
Draw a bar diagram to represent the situation.
Answer:
It is given that a 132-inch board is cut into two pieces and one piece is 3 times the length of the other
Now,
Let the length of 1 piece be x inches
So,
The length of the other piece is: 3x inches
So,
The representation of the given situation in the form of an equation is:
3x + x = 132
Hence,
The representation of the above equation in the form of a bar diagram is:

PART B
Write and solve an equation to find the length of the shorter piece.
Answer:
From part (a),
The equation that represents the given situation is:
3x + x = 132
4x = 132
Divide by 4 into both sides
So,
x = \(\frac{132}{4}\)
x = 33 inches
Hence,from the above,
We can conclude that the length of the shorter piece is: 33 inches

Lesson 2.2 Solve Equations with Variables on Both Sides

Solve & Discuss It!
Jaxson and Bryon collected an equal amount of money during a car wash. They collected cash and checks as shown below. If each check is written for the same amount, x, what is the total amount of money collected by both boys? Explain.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 18
I can… solve equations with variables on both sides of the equal sign.
Answer:
It is given that Jaxson and Bryon collected an equal amount of money during the car wash.
It is also given that they collected cash and checks and each check is written for the same amount x
So,
The amount earned by Jaxson = The amount earned by Bryon
Now,
From the given figure,
The amount earned by Jaxson = The amount earned by cash + The amount earned by checks
= 15 + 14x
The amount earned by Bryon = The amount earned by cash + The amount earned by checks
= 50 + 7x
So,
Now,
15 + 14x = 50 + 7x
Subtract with 7x on both sides
15 + 14x – 7x = 50 + 7x – 7x
15 + 7x = 50
Subtract with 15 on both sides
15 + 7x – 15 = 50 – 15
7x = 35
Divide by 7 on both sides
\(\frac{7}{7}\)x = \(\frac{35}{7}\)
x = 5
So,
The total amount of money collected by both boys = 15 +14x + 50 + 7x
= 21x + 65
= 21 (5) + 65
= 105 + 65
= $170
Hence, from the above,
We can conclude that the total amount earned by both the boys is: $170

Reasoning
How can you use an equation to show that expressions are equal?
Answer:
Combine any like terms on each side of the equation i.e., x-terms with x-terms and constants with constants. Arrange the terms in the same order, usually x-term before constants.
If all of the terms in the two expressions are identical, then the two expressions are equivalent.

Focus on math practices
Model with Math What expressions can you write to represent the amount of money collected by each boy? How can you use these expressions to write an equation?
Answer:
From the given figure,
We can observe that the two boys earned cash and checks
So,
The total amount earned by any boy = The amount earned due to cash + The amount earned due to checks
Now,
The amount earned by Jaxson = The amount earned by cash + The amount earned by checks
= 15 + 14x
The amount earned by Bryon = The amount earned by cash + The amount earned by checks
= 50 + 7x
Now,
It is given that the amount earned by both boys are equal
So,
The amount earned by Jaxson = The amount earned by Bryon
15 + 14x = 50 + 7x
Rearrange the like terms
14x – 7x = 50 – 15
7x = 35
Hence, from the above,
We can conclude that the representation of the amount collected by each boy in the form of the equation is:
7x = 35

Essential Question
How do you use inverse operations to solve equations with variables on both sides?
Answer:
The “Inverse operations” allow us to undo what has been done to the variable
Example:
Solve:
x+3=8
From the above equation,
We can observe that 
3 has been added to the variable, x.
We know that,
The inverse of addition is subtraction
So,
By subtracting 3, We can undo the addition.
Now,
After 3 was added, the result was equal to 8.
We undo the addition, by subtracting 3 and see that, the starting amount was 5

Try It!

Class A was given a sunflower with a height of 8 centimeters that grows at a rate of 3\(\frac{1}{2}\) centimeters per week. Class B was given a sunflower with a height of 10 centimeters that grows at a rate of 3\(\frac{1}{4}\) centimeters per week. After how many weeks are the sunflowers the same height?
Let w= the number of weeks.
____ w + 8 = _____ w + 10
_____ w + 8 = 10
_____ w = _____
w = _____
The sunflowers are the same height after ________ weeks.
Answer:
It is given that
Class A was given a sunflower with a height of 8 centimeters that grows at a rate of 3\(\frac{1}{2}\) centimeters per week and class B was given a sunflower with a height of 10 centimeters that grows at a rate of 3\(\frac{1}{4}\) centimeters per week.
Now,
Let the number of weeks be w
So,
The height of a sunflower of class A after w weeks = 3\(\frac{1}{2}\)w + 8
We know that,
3\(\frac{1}{2}\) = \(\frac{7}{2}\)
So,
The height of a sunflower of class A after w weeks = \(\frac{7}{2}\)w + 8
Now,
The height of a sunflower of class B after w weeks = 3\(\frac{1}{4}\)w + 10
We know that,
3\(\frac{1}{4}\) = \(\frac{13}{4}\)
So,
The height of a sunflower of class A after w weeks = \(\frac{13}{4}\)w + 10
Now,
To make the height of a sunflower from both classes equal,
The height of sunflower of class A after w weeks = The height of sunflower of class B after w weeks
\(\frac{7}{2}\)w + 8 = \(\frac{13}{4}\)w + 10
Rearrange the like terms
\(\frac{7}{2}\)w – \(\frac{13}{4}\)w = 10 – 8
\(\frac{14 – 13}{4}\)w = 2
\(\frac{1}{4}\)w = 2
Multiply with 4 on both sides
\(\frac{4}{4}\)w = 2 (4)
w = 8 weeks
Hence, from the above,
We can conclude that after 8 weeks, the sunflowers of class A and class B are of the same height

Convince Me!
How can you check your work to make sure the value of the variable makes the equation true? Explain.
Answer:
To make a true equation, check your math to make sure that the values on each side of the equals sign are the same. Ensure that the numerical values on both sides of the “=” sign are the same to make a true equation.
Examples:
a) 9 = 9 is a true equation
b) 5 + 4 = 9 is a true equation

Try It!

Solve the equation 96 – 4.5y – 3.2y = 5.6y + 42.80.
Answer:
The given equation is:
96 – 4.5y – 3.2y = 5.6y + 42.80
Now,
Rearrange the like terms at one side i.e., y-terms to one side and the constant terms to other side
So,
-5.6y – 4.5y – 3.2y = 42.80 – 96
-13.3y = -53.2
13.3y = 53.2
Divide by 13.3 into both sides
So,
\(\frac{13.3}{13.3}\)y = \(\frac{53.2}{13.3}\)
y = 4
Hence, from the above,
We can conclude that the value of y is: 4

KEY CONCEPT

When two expressions represent equal quantities, they can be set equal to each other. Then you can use inverse operations and properties of equality to combine like terms and solve for the unknown.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 19
3x + 15 = 4x + 12
3x – 3x + 15 = 4x – 3x + 12
15 = x + 12
15 – 12 = x + 12 – 12
3 = x

Do You Understand?
Question 1.
Essential Question How do you use inverse operations to solve equations with variables on both sides?
Answer:
The “Inverse operations” allow us to undo what has been done to the variable
Example:
Solve:
x+3=8
From the above equation,
We can observe that 
3 has been added to the variable, x.
We know that,
The inverse of addition is subtraction
So,
By subtracting 3, We can undo the addition.
Now,
After 3 was added, the result was equal to 8.
We undo the addition, by subtracting 3 and see that, the starting amount was 5

Question 2.
Reasoning Why are inverse operations and properties of equality important when solving equations? Explain.
Answer:
An “Inverse operation” is two operations that undo each other
Ex: Addition and Subtraction or Multiplication and Division.
You can perform the same inverse operation on each side of an equivalent equation without changing the equality.
This gives us a couple of properties that hold true for all equations.

Question 3.
Model with Math Cynthia earns $680 in commissions and is paid $10.25 per hour. Javier earns $410 in commissions and is paid $12.50 per hour. What will you find if you solve for x in the equation 10.25x + 680 = 12.5x + 410?
Answer:
It is given that
Cynthia earns $680 in commissions and is paid $10.25 per hour. Javier earns $410 in commissions and is paid $12.50 per hour.
It is also given that
The representation of the given situation in the form of the equation is:
10.25x + 680 = 12.5x + 410
From the above equation,
We can observe that
10.25x is the amount paid to Cynthia per hour and x is the number of hours
Hence, from the above,
We can conclude that the variable x represents the “Number of hours”

Do You Know How?
Question 4.
Maria and Liam work in a banquet hall. Maria earns a 20% commission on her food sales. Liam earns a weekly salary of $625 plus a 10% commission on his food sales. What amount of food sales will result in Maria and Liam earning the same amount for the week?
Answer:
It is given that
Maria earns a 20% commission on her food sales. Liam earns a weekly salary of $625 plus a 10% commission on his food sales.
So,
To find the number of food sales that will result in Maria and Liam earning the same amount for the week,
20%x = $625 + 10%x
Where,
x is the number of food sales
So,
\(\frac{20}{100}\)x = $625 + \(\frac{10}{100}\)x
Rearrange the like terms
\(\frac{20 – 10}{100}\)x = $625
\(\frac{10}{100}\)x = $625
\(\frac{1}{10}\)x = $625
Multiply with 10 on both sides
So,
\(\frac{10}{10}\)x = $625 (10)
x = $6,250
Hence, from the above,
We can conclude that the number of food sales that will make the same amount in the week for Maria and Liam is: $6,250

Question 5.
Selma’s class is making care packages to give to victims of a natural disaster. Selma packs one box in 5 minutes and has already packed 12 boxes. Her friend Trudy packs one box in 7 minutes and has already packed 18 boxes. How many more minutes does each need to work in order to have packed the same number of boxes?
Answer:
It is given that
Selma’s class is making care packages to give to victims of a natural disaster. Selma packs one box in 5 minutes and has already packed 12 boxes. Her friend Trudy packs one box in 7 minutes and has already packed 18 boxes.
Now,
Let x be the number of  more minutes that each has to work so that they have the same number of boxes
So,
To find the more minutes each need to work in order to have packed the same number of boxes,
\(\frac{x}{5}\) + 12 = \(\frac{x}{7}\) + 18
Rearrange the like terms
So,
\(\frac{x}{5}\) – \(\frac{x}{7}\) = 18 – 12
\(\frac{7x – 5x}{35}\) = 6
\(\frac{2x}{35}\) = 6
Divide by 35 into both sides
So,
2x = 6 (35)
Divide by 2 into both sides
So,
x = \(\frac{6 (35)}{2}\)
x = 3 (35)
x = 105 minutes
Hence, from the above,
We can conclude that the number of more minutes that each need to work so that the number of boxes becomes equal is: 105 minutes

Question 6.
Solve the equation –\(\frac{2}{5}\)x + 3 = \(\frac{2}{3}\)x + \(\frac{1}{3}\).
Answer:
The given equation is:
–\(\frac{2}{5}\)x + 3 = \(\frac{2}{3}\)x + \(\frac{1}{3}\)
Rearrange the like terms
So,
\(\frac{2}{3}\)x + \(\frac{2}{5}\)x = 3 – \(\frac{1}{3}\)
\(\frac{10 + 6}{15}\)x = \(\frac{9 – 1}{3}\)
\(\frac{16}{15}\)x = \(\frac{8}{3}\)
Multiply with \(\frac{15}{16}\) on both sides
x = \(\frac{8}{3}\) × \(\frac{15}{16}\)
x = \(\frac{8 × 15}{3 × 16}\)
x = \(\frac{5}{2}\)
Hence, from the above,
We can conclude that the value of x is: \(\frac{5}{2}\)

Question 7.
Solve the equation -2.6b + 4 = 0.9b – 17.
Answer:
The given equation is:
-2.6b + 4 = 0.9b – 17
Rearrange the like terms
So,
0.9b + 2.6b = 17 + 4
3.5b = 21
Divide by 3.5 into both sides
So,
\(\frac{3.5}{3.5}\)b = \(\frac{21}{3.5}\)
b = 6
Hence, from the above,
We can conclude that the value of b is: 6

Practice & Problem Solving

Leveled Practice In 8 and 9, solve each equation.
Question 8.
6 – 4x = 6x – 8x + 2
6 – 4x = ____ + 2
6 = _____ + 2
____ = _____
_______ = x
Answer:
The given equation is:
6 – 4x = 6x – 8x + 2
So,
6 – 4x = 2 – 2x
Rearrange the like terms
So,
4x – 2x = 6 – 2
2x = 4
Divide by 2 into both sides
So,
\(\frac{2}{2}\)x = \(\frac{4}{2}\)
x = 2
Hence, from the above,
We can conclude that the value of x is: 2

Question 9.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 20
Answer:
The given equation is:
\(\frac{5}{3}\)x + \(\frac{1}{3}\)x = 13\(\frac{1}{3}\) + \(\frac{8}{3}\)x
Rearrange the like terms
So,
\(\frac{5 + 1}{3}\)x – \(\frac{8}{3}\)x = 13\(\frac{1}{3}\)
\(\frac{6 – 8}{3}\)x = 13\(\frac{1}{3}\)
–\(\frac{2}{3}\)x = \(\frac{40}{3}\)
Multiply with 3 on both sides
So,
-2x = 40
divide by -2 into both sides
So,
x = \(\frac{-40}{2}\)
x = -20
Hence, from the above,
We can conclude that the value of x is: -20

Question 10.
Two towns have accumulated different amounts of snow. In Town 1, the snow depth is increasing by 3\(\frac{1}{2}\) inches every hour. In Town 2, the snow depth is increasing by 2\(\frac{1}{4}\) inches every hour. In how many hours will the snowfalls of the towns be equal?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 21
Answer:
It is given that
Two towns have accumulated different amounts of snow. In Town 1, the snow depth is increasing by 3\(\frac{1}{2}\) inches every hour. In Town 2, the snow depth is increasing by 2\(\frac{1}{4}\) inches every hour.
Now,
Let x be the number of hours
So,
To make the snowfalls of the two towns equal,
5 + 3\(\frac{1}{2}\)x = 6 + 2\(\frac{1}{4}\)x
We know that,
3\(\frac{1}{2}\) = \(\frac{7}{2}\)
2\(\frac{1}{4}\) = \(\frac{9}{4}\)
So,
\(\frac{7}{2}\)x – \(\frac{9}{4}\)x = 6 – 5
\(\frac{14 – 9}{4}\)x = 1
\(\frac{5}{4}\)x = 1
Multiply with \(\frac{4}{5}\) on both sides
So,
x = \(\frac{4}{5}\)
x = 0.8 hours
Hence, from the above,
We can conclude that after 0.8 hours, the snowfalls of the two towns will be equal

Question 11.
Solve the equation 5.3g + 9 = 2.3g + 15.
a. Find the value of g.
Answer:
The given equation is:
5.3g + 9 = 2.3g + 15
Rearrange the like terms
So,
5.3g – 2.3g = 15 – 9
3.0g = 6
Divide by 3 into both sides
\(\frac{3}{3}\)g = \(\frac{6}{3}\)
g = 2
Hence, from the above,
We can conclude that the value of g is: 2

b. Explain how you can check that the value · you found for g is correct. If your check does not work, does that mean that your result is incorrect? Explain.
Answer:
From part (a),
We get the value of g : 2
So,
Whether the value of g is correct or not, put it in the given equation
If LHS = RHS,
Then, your check is correct. Otherwise, your check is not correct
Now,
5.3g + 9 = 2.3g + 15
Put, g = 2
So,
5.3 (2) + 9 = 2.3 (2) + 15
10.6 + 9 = 4.6 + 15
19.6 = 19.6
Hence, from the above,
We can conclude that the check is correct

Question 12.
Solve the equation 6 – 6x = 5x – 9x – 2.
Answer:
The given equation is:
6 – 6x = 5x – 9x – 2
So,
6 – 6x = -4x – 2
Rearrange the like terms
So,
-4x + 6x = 6 + 2
2x = 8
Divide by 2 into both sides
So,
\(\frac{2}{2}\)x = \(\frac{8}{2}\)
x = 4
Hence, from the above,
We can conclude that the value of x is: 4

Question 13.
Model with Math The population of one town in Florida is 43,425. About 125 people move out of the town each month. Each month, 200 people on average move into town. A nearby town has a population of 45,000. It has no one moving in and an average of 150 people moving away every month. In about how many months will the population of the towns be equal? Write an equation that represents this situation and solve it.
Answer:
It is given that
The population of one town in Florida is 43,425. About 125 people move out of the town each month. Each month, 200 people on average move into town. A nearby town has a population of 45,000. It has no one moving in and an average of 150 people moving away every month.
Now,
Let the population that are moving in and moving out be x
We know that,
Moving in will be positive and Moving out will be negative
So,
The population of one town in Florida = 43,425 + 200x – 125x
The population of a nearby town = 45,000 – 150x
So,
To find out after how many months, they will be equal,
43,425 + 200x – 125x = 45,000 – 150x
43,425 + 75x = 45,000 – 150x
Rearrange the like terms
So,
150x + 75x = 45,000 – 43,425
225x = 1,575
Divide by 225 into both sides
\(\frac{225}{225}\)x = \(\frac{1,575}{225}\)
x = 7
Hence, from the above,
We can conclude that after 7 months, the population of the towns will be equal

Question 14.
Veronica is choosing between two health clubs After how many months will the total cost for each health club be the same?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 22
Answer:
It is given that Veronica is choosing between two health clubs
Now,
Let x be the number of months so that the cost for the two health clubs will be the same
Now,
The total health cost of Yoga studio A = 22 + 24.50x
The total health cost of Yoga studio B = 47 + 18.25x
So,
To find out after how many months, the total cost for the two health clubs will be the same,
22 + 24.50x = 47 + 18.25x
Rearrange the like terms
So,
47 – 22 = 24.50x – 18.25x
25 = 6.25x
Divide by 25 into both sides
So,
\(\frac{25}{25}\) = \(\frac{6.25}{25}\)x
1 = 0.25x
\(\frac{x}{4}\) = 1
x = 4
Hence, from the above,
We can conclude that after 4 months, the total cost for the two health clubs will be the same

Question 15.
Higher-Order Thinking The price of Stock A at 9 A.M. was $12.73. Since then, the price has been increasing at the rate of $0.06 per hour. At noon, the price of Stock B was $13.48. It begins to decrease at the rate of $0.14 per hour. If the stocks continue to increase and decrease at the same rates, in how many hours will the prices of the stocks be the same?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 23
Answer:
It is given that
The price of Stock A at 9 A.M. was $12.73. Since then, the price has been increasing at the rate of $0.06 per hour. At noon, the price of Stock B was $13.48. It begins to decrease at the rate of $0.14 per hour.
Now,
Let x be the number of hours
So,
The price of stock A = $12.73 + $0.06x (Since it is increasing)
The price of stock B = $13.48 – $0.14x (Since it is decreasing)
Now,
To find out after how many hours, the prices will be the same,
$12.73 + $0.06x = $13.48 – $0.14x
Rearrange the like terms
So,
$13.48 – $12.73 = $0.14x + $0.06x
$0.75 = $0.2x
Divide by 0.2 into both sides
So,
x = \(\frac{0.75}{0.2}\)
x = 3.75
x = 3.60 + 0.15
x = 4 hours 15 minutes
Hence, from the above,
We can conclude that after 4 hours 15 minutes, the prices of the stocks will be equal

Assessment Practice
Question 16.
In an academic contest, correct answers earn 12 points and incorrect answers lose 5 points. In the final round, School A starts with 165 points and gives the same number of correct and incorrect answers. School B starts with 65 points and gives no incorrect answers and the same number of correct answers as School A. The game ends with the two schools tied.
PART A
Which equation models the scoring in the final round and the outcome of the contest?
A. 12x + 5x – 165 = -12x + 65
B. 12x – 5x + 165 = 12x + 65
C. 5x – 12x + 165 = 12x + 65
D. 12x – 5x – 165 = 12x + 65
Answer:
It is given that
In an academic contest, correct answers earn 12 points and incorrect answers lose 5 points. In the final round, School A starts with 165 points and gives the same number of correct and incorrect answers. School B starts with 65 points and gives no incorrect answers and the same number of correct answers as School A. The game ends with the two schools tied.
Now,
Let the number of answers be x
We know that,
The points earned for the correct answers will be positive whereas, for the negative answers, they will be negative
So,
For school A,
The number of answers is:
12x – 5x = -165
12x – 5x + 165 = 0
For school B,
The number of answers is:
12x + 0 = -65
12x + 65 = 0
Now,
It is given that the two schools are tied
So,
12x – 5x + 165 = 12x + 65
Hence, from the above,
We can conclude that option B matches the above-given situation

PART B
How many answers did each school get correct in the final round?
Answer:
From part (a),
The equation that models the scoring and outcome of the contest is:
12x – 5x + 165 = 12x + 65
Now,
Rearrange the terms
So,
12x – 12x – 5x = 65 – 165
-5x = -100
5x = 100
Divide by 5 into both sides
So,
\(\frac{5}{5}\)x = \(\frac{100}{5}\)
x = 20
Hence, from the above,
We can conclude that each school gets 20 correct answers in the final round

Lesson 2.3 Solve Multistep Equations

Solve & Discuss It!
A water tank fills through two pipes. Water flows through one pipe at a rate of 25,000 gallons an hour and through the other pipe at 45,000 gallons an hour. Water leaves the system at a rate of 60,000 gallons an hour.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 24
I can… solve multistep equations and pairs of equations using more than one approach.
There are 3 of these tanks, and each tank holds 1 million gallons. Each tank is half full. Water is entering and leaving a tank at the maximum amounts. Determine the number of hours, x, it will take to fill all 3 tanks.
Answer:
It is given that
A water tank fills through two pipes. Water flows through one pipe at a rate of 25,000 gallons an hour and through the other pipe at 45,000 gallons an hour. Water leaves the system at a rate of 60,000 gallons an hour and there are 3 of these tanks, and each tank holds 1 million gallons. Each tank is half full. Water is entering and leaving a tank at the maximum amounts.
Now,
The capacity of each tank = \(\frac{1 million}{2}\) (Since the tank is half-full)
We know that,
1 million = 10 lakhs
So,
The capacity of each tank is: 5 Lakh gallons
So,
The capacity of 3 tanks = 5 Lakh gallons (3)
= 15 Lakh gallons
Now,
The rate of flow of each tank = (The rate of flow of inlet pipes) + (The rate of flow of outlet pipes)
We know that,
The rate of flow for the inlet pipe will be: Positive
The rate of flow for the outlet pipe will be: Negative
So,
The rate of flow of each tank = (45,000 + 25,000) – 60,000
= 70,000 – 60,000
= 10,000 gallons per hour
Since the three pipes are the same, the rate of flow will also be the same
So,
The rate of flow of three tanks = 10,000 (3)
= 30,000 gallons per hour
Now,
It is given that the number of hours is: x
So,
The number of hours took to fill all the three tanks = \(\frac{ The capacity of three tanks } { The rate of flow of the three tanks }\)
x = \(\frac{15,00,000}{30,000}\)
x = 50 hours
Hence, from the above,
We can conclude that the number of hours took to fill the three tanks is: 50 hours

Reasoning
Can you solve the problem in more than one way?
Answer:
Yes, we can solve the problem in more than one way
The first way:
First, calculate the capacity and the rate of flow of each tank and multiply both the quantities with 3 since it is for 3 tanks
So,
We will get the time took to fill the three tanks
The second way:
Calculate the capacity and the rate of the flow of each tank and also find the time taken to fill that tank and multiply the time taken by 3 to get the time taken to fill the three tanks

Focus on math practices
Use Structure What are two different ways to simplify the expression 4(3x + 7x + 5) so that it equals 40x – 20? Explain.
Answer:
The given expression is:
4 (3x + 7x + 5)
A)
The first way:
We know that,
The distributive property is:
a (b + c) = ab + ac
So,
4 (3x + 7x + 5)
= 4 (3x) + 4 (7x) + 4 (5)
= 12x + 28x + 20
= 40x + 20
B)
The second way:
4 (3x + 7x + 5)
First, simplify the expression in the brackets
So,
4 (3x + 7x + 5)
= 4 (10x + 5)
= 4 (10x) + 4(5)
= 40x + 20

Essential Question
How can you use the Distributive Property to solve multistep equations?
Answer:
Let A, B, and C be the three variables
Now,
We know that,
The Distributive Property of multiplication is:
A (B + C) = AB + AC
(A + B) C = AC + BC
(A + C) B = AB + BC

Try It!

Solve the equation 3(x – 5) – 5x = -25 + 6x.
3_____ + 3 ∙ ______ – 5x = – 25 + 6x
_____ – 5x = – 25 + 6x
______ x – 15 = – 25 + 6x
______ – 15 = -25 + _____ x
______ = _____ x ______
x = _____ or ______
Answer:
The given equation is:
3 (x – 5) – 5x = -25 + 6x
3 (x) – 3 (5) – 5x = -25 + 6x
3x – 15 – 5x = -25 + 6x
-15 – 2x = -25 + 6x
Rearrange the like terms
So,
-15 + 25 = 6x + 2x
8x = 10
Divide by 8 into both sides
x = \(\frac{10}{8}\)
x = \(\frac{5}{4}\)
Hence, from the above,
We can conclude that the value of x is: \(\frac{5}{4}\)

Convince Me!
Can you add x to -5x on the left side of the equation as the first step? Explain.
Answer:
No, we can’t add x to the -5x because from the given equation,
We are getting
3x – 5x
So,
We have to add 3x and not x to -5x

Try It!

Solve the equation -3(-7 – x) = \(\frac{1}{2}\)(x + 2).
Answer:
The given equation is:
-3 (-7 – x) = \(\frac{1}{2}\) (x + 2)
So,
-3 [-(x + 7)] = \(\frac{1}{2}\) (x + 2)
We know that,
– * – = +
So,
3 (x + 7) = \(\frac{1}{2}\) (x + 2)
Multiply with 2 on both sides
So,
6 (x + 7) = x + 2
6 (x) + 6 (7) = x + 2
6x + 42 = x + 2
Rearrange the like terms
6x – x = 2 – 42
5x = -40
Divide by 5 into both sides
So,
x = \(\frac{-40}{5}\)
x = -8
Hence, from the above,
We can conclude that the value of x is: -8

KEY CONCEPT

When solving multistep equations, sometimes you distribute first and then combine like terms.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 25
Sometimes you combine like terms first and then distribute.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 26

Do You Understand?
Question 1.
Essential Question How can you use the Distributive Property to solve multistep equations?
Answer:
Let A, B, and C be the three variables
Now,
We know that,
The Distributive Property of multiplication is:
A (B + C) = AB + AC
(A + B) C = AC + BC
(A + C) B = AB + BC

Question 2.
Reasoning What is the first step when solving the equation 3(3x – 5x) + 2 = -8?
Answer:
The given equation is:
3 (3x – 5x) + 2 = -8
Use the distributive property of multiplication
So,
3 (3x) – 3(5x) + 2 = -8 ——–> First step when solving the above equation

Question 3.
Use Structure How can you use the order of operations to explain why you cannot combine the variable terms before using the Distributive Property when solving the equation 7(x + 5) – x = 42?
Answer:
The given equation is:
7 (x + 5) – x = 42
To find the order of operations, We have to use the BODMAS rule
So,
From the above equation,
We will first solve the expression present in the brackets, then add, and then subtract
We know that,
We can do any operation only on the like terms
We know that,
The “Like terms” are the terms that have the same exponent
So,
For the above equation,
We can not combine the terms before using the distributive property
Now,
7 (x) + 7 (5) – x = 42
7x + 35 – x = 42
6x + 35 = 42
Subtract with 35 on both sides
6x = 42 – 35
6x = 7
Divide by 6 into both sides
So,
x = \(\frac{7}{6}\)
Hence, from the above,
We can conclude that the value of x is: \(\frac{7}{6}\)

Do You Know How?
Question 4.
Solve the equation 3x + 2 = x + 4(x + 2).
Answer:
The given equation is:
3x + 2 = x + 4 (x + 2)
3x + 2 = x + 4 (x) + 4 (2)
3x + 2 = x + 4x + 8
3x + 2 = 5x + 8
Rearrange the like terms
So,
5x – 3x = -8 + 2
2x = -6
Divide by 2 into both sides
So,
x = \(\frac{-6}{2}\)
x = -3
Hence, from the above,
We can conclude that the value of x is: -3

Question 5.
Solve the equation -3(x – 1) + 7x = 27.
Answer:
The given equation is:
-3 (x – 1) + 7x = 27
So,
-3 (x) + 3 (1) + 7x = 27
-3x + 3 + 7x = 27
4x + 3 = 27
Subtract with 3 on both sides
So,
4x = 27 – 3
4x = 24
Divide by 4 into both sides
So,
x = \(\frac{24}{4}\)
x = 6
Hence, from the above,
We can conclude that the value of x is: 6

Question 6.
Solve the equation \(\frac{1}{3}\)(x + 6) = \(\frac{1}{2}\)(x – 3).
Answer:
The given equation is:
\(\frac{1}{3}\)(x + 6) = \(\frac{1}{2}\)(x – 3)
Multiply with 6 on both sides so that we can make the fractions as integers (It is not compulsory to multiply with only 6. You can also multiply with any number that is multiple of both 2 and 3)
So,
\(\frac{6}{3}\) (x + 6) = \(\frac{6}{2}\) (x – 3)
2 (x + 6) = 3 (x – 3)
2 (x) + 2 (6) = 3 (x) – 3 (3)
2x + 12 = 3x – 9
Rearrange the like terms
So,
3x – 2x = 12 + 9
x = 21
Hence,f rom the above,
We can conclude that the value of x is: 21

Question 7.
Solve the equation 0.25(x + 4) – 3 = 28.
Answer:
The given equation is:
0.25 (x + 4) – 3 = 28
Add with 3 on both sides
So,
0.25 (x + 4) = 28 + 3
0.25 (x + 4) = 31
We know that,
0.25 = \(\frac{1}{4}\)
So,
\(\frac{x + 4}{4}\) = 31
Multiply with 4 on both sides
So,
x + 4 = 31 (4)
x + 4 = 124
Subtract with 4 on both sides
So,
x = 124 – 4
x = 120
Hence, from the above,
We can conclude that the value of x is: 120

Practice & Problem Solving

Leveled Practice In 8-10, find the value of x.
Question 8.
Lori bought sunglasses and flip-flops at a half-off sale. If she spent a total of $21 on the two items, what was the original price of the sunglasses?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 27
The original price of the sunglasses was _________.
Answer:
It is given that
Lori bought sunglasses and flip-flops at a half-off sale. If she spent a total of $21 on the two items
Now,
Let x be the price of sunglasses
It is also given that
the price of flipflops is: $24
So,
\(\frac{1}{2}\) (x + $24) = $21
Multiply with 2 on both sides
So,
x + $24 = $21 (2)
x + $24 = $42
Subtract with $24 on both sides
So,
x = $42 – $24
x = $18
Hence, from the above,
We can conclude that the price of sunglasses is: $18

Question 9.
Use the Distributive Property to solve the equation 28 – (3x + 4) = 2(x + 6) + x.
28 – ______ x – _____ = 2x + _____ + x
24 – _____x = ______x + ______
24 – _____x = ______
_____ x = ______
x = ______
Answer:
The given equation is:
28 – (3x + 4) = 2 (x + 6) + x
By using the distributive property,
28 – 3x – 4  = 2 (x) + 2 (6) + x
24 – 3x = 2x + 12 + x
24 – 3x = 3x + 12
Rearrange the like terms
So,
3x + 3x = 24 – 12
6x = 12
Divide by 6 into both sides
So,
x = \(\frac{12}{6}\)
x = 2
Hence, from the above,
We can conclude that the value of x is: 2

Question 10.
Use the Distributive Property to solve the equation 3(x – 6) + 6 = 5x – 6.
x – _____ + 6 = 5x – ______
_____ x – _____ = 5x – _______
_____ x – _____ = _______
______ x = _______
x = ________
Answer:
The given equation is:
3 (x – 6) + 6 = 5x – 6
By using the Distributive property,
3 (x) – 3 (6) + 6 = 5x – 6
3x – 18 + 6 = 5x – 6
3x – 12 = 5x – 6
Rearrange the like terms
So,
5x – 3x = 6 – 12
2x = -6
x = \(\frac{-6}{2}\)
x = -3
Hence, from the above,
We can conclude that the value of x is: -3

Question 11.
What is the solution to -2.5(4x – 4) = -6?
Answer:
The given equation is:
-2.5 (4x – 4) = -6
So,
-2.5 (4x) + 2.5 (4) = -6
-10x + 10 = -6
Subtract with 10 on both sides
So,
-10x = -6 – 10
-10x = -16
10x = 16
Divide by 10 into both sides
So,
x = \(\frac{16}{10}\)
x = 1.6
Hence, from the above,
We can conclude that the solution of the given equation is: 1.6

Question 12.
What is the solution to the equation 3(x + 2) = 2(x + 5)?
Answer:
The given equation is:
3 (x + 2) = 2 (x + 5)
So,
3 (x) + 3 (2) = 2 (x) + 2 (5)
3x + 6 = 2x + 10
Rearrange the like terms
So,
3x – 2x = 10 – 6
x = 4
Hence, from the above,
We can conclude that the solution of the given equation is: 4

Question 13.
Solve the equation \(\frac{1}{6}\)(x – 5) = \(\frac{1}{2}\)(x + 6).
Answer:
The given equation is:
\(\frac{1}{6}\)(x – 5) = \(\frac{1}{2}\)(x + 6)
Multiply with 6 on both sides
So,
x – 5 = 3 (x + 6)
x – 5 = 3 (x) + 3 (6)
x – 5 = 3x + 18
Rearrange the like terms
So,
x – 3x = 18 + 5
-2x = 23
Divide by -2 into both sides
So,
x = –\(\frac{23}{2}\)
Hence, from the above,
We can conclude that the value of x for the given equation is: –\(\frac{23}{2}\)

Question 14.
Solve the equation 0.6(x + 2) = 0.55(2x + 3).
Answer:
The given equation is:
0.6 (x + 2) = 0.55 (2x + 3)
So,
0.6 (x) + 0.6 (2) = 0.55 (2x) + 0.55 (3)
0.6x + 1.2 = 1.10x + 1.65
Rearrange the like terms
So,
1.10x – 0.6x = 1.2 – 1.65
0.5x = -0.45
Divide by 0.5 into both sides
So,
x = \(\frac{-0.45}{0.5}\)
x = -0.9
Hence, from the above,
We can conclud ethat the value of x is: -0.9

Question 15.
Solve the equation 4x – 2(x – 2) = -9 + 5x – 8.
Answer:
The given equation is:
4x – 2 (x – 2) = -9 + 5x – 8
So,
4x – 2 (x) + 2 (2) = -9 + 5x – 8
4x – 2x + 4 = 5x – 17
2x + 4 = 5x – 17
Rearrange the like terms
So,
5x – 2x = 17 + 4
3x = 21
Divide by 3 into both sides
So,
x = \(\frac{21}{3}\)
x = 7
Hence, from the above,
We can conclude that the value of x is: 7

Question 16.
Use the Distributive Property to solve the equation 2(m + 2) = 22. Describe what it means to distribute the 2 to each term inside the parentheses.
Answer:
The given equation is:
2 (m + 2) = 22
We know that,
By using the distributive property of multiplication,
A (B + c) = AB + AC
So,
2 (m) + 2 (2) = 22
2m + 4 = 22
2m = 22 – 4
2m = 18
m = \(\frac{18}{2}\)
m = 9
Hence, from the above,
We can conclude that the value of m is: 9

Question 17.
What is Peter’s number?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 28
Answer:
Let peter’s number be x
So,
According to the given statement,
-3 (x – 12) = -54
3 (x – 12) = 54
3x – 3 (12) = 54
3x – 36 = 54
3x = 36 + 54
3x = 90
x = \(\frac{90}{3}\)
x = 30
Hence, from the above,
We acn conclude that peter’s number is: 30

Question 18.
Higher Order Thinking Use the Distributive Property to solve the equation \(\frac{4x}{5}\) – x = \(\frac{x}{10}\) – \(\frac{9}{2}\)
Answer:
The given equation is:
\(\frac{4x}{5}\) – x = \(\frac{x}{10}\) – \(\frac{9}{2}\)
Rearrange the like terms
So,
\(\frac{4x}{5}\) – x – \(\frac{x}{10}\) = –\(\frac{9}{2}\)
\(\frac{7x}{10}\) – x = –\(\frac{9}{2}\)
–\(\frac{3x}{10}\) = –\(\frac{9}{2}\)
Multiplywith \(\frac{10}{3}\) on both sides
x = \(\frac{9 × 10}{2 × 3}\)
x = 15
Hence, from the above,
We can conclude that the value of x is: 15

Assessment Practice
Question 19.
How many solutions does the equation -2(x + 4) = -2(x + 4) – 6 have?
Answer:
The given equation is:
-2 (x + 4) = -2 (x + 4) – 6
So,
-2 (x) – 2 (4) = -2 (x) – 2 (4) – 6
-2x – 8 = -2x – 8 – 6
Rearrange the like terms
So,
-2x + 2x – 8 + 8 = -6
0 = -6
Hence, from the above,
We can conclude that there are no solutions for the given equation

Question 20.
Solve the equation 3(x + 4) = 2x + 4x – 6 for x.
Answer:
The given equation is:
3 (x + 4) = 2x + 4x – 6
So,
3 (x) + 3 (4) = 6x – 6
3x + 12 = 6x – 6
Rearrange the like terms
So,
6x – 3x = 12 + 6
3x = 18
x = \(\frac{18}{3}\)
x = 6
Hence, from the above,
We can conclude that the solution of the given equation is: 6

Lesson 2.4 Equations with No Solutions or Infinitely Many Solutions

Explore It!
The Great Karlo called twins Jasmine and James onto the stage. Jasmine, multiply your age by 3 and add 6. Then multiply this sum by 2. James, multiply your age by 2 and add 4. Then multiply this sum by 3. I predict you will both get the same number!
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 29
I can… determine the number of solutions an equation has.

A. Write expressions to represent Great Karlo’s instructions to each twin.
Answer:
It is given that
The Great Karlo called the twins Jasmine and James onto the stage. Jasmine, multiply your age by 3 and add 6. Then multiply this sum by 2. James, multiply your age by 2 and add 4. Then multiply this sum by 3.
Now,
Great Karlo’s instructions to Jasmine:
Let the age of Jasmine be x
Step 1:
Multiply your age by 3 and add 6
3x + 6
Step 2:
Multiply step 1 with 2
2 (3x +6)
So,
The expression representing the age of Jasmine is: 2 (3x + 6)
Great Karlo’s instructions to James
Let the age of James be x
Step 1:
Multiply your age by 2 and add 4
2x + 4
Step 2:
Multiply step 1 with 3
3 (2x +4)
So,
The expression representing the age of James is: 3 (2x + 4)
Hence, from the above,
We can conclude that the expressions that represent the Great Karlo’s instruction to each twin are:
For Jasmine —–> 2 (3x + 6)
For James ——-> 3 (2x + 4)

B. Choose 4 whole numbers for the twins’ age and test each expression. Make a table to show the numbers you tried and the results.
Answer:
It is given that the great Karlo predicted that the twins will get the same number
So,
2 (3x + 6) = 3 (2x + 4)
2 (3x) + 2 (6) = 3 (2x) + 3 (4)
6x + 12 = 6x + 12
Hence,
The table to show the numbers tried for Jasmine’s and James ages and the results are:

C. What do you notice about your results?
Answer:
From the table that is present in part (b),
We can observe that the ages of Jasmine and James are the same

Focus on math practices
Make Sense and Persevere Choose three more values and use them to evaluate each expression. What do you notice? Do you think this is true for all values? Explain.
Answer:
The table that represents three more values of Jasmine’s and James’ ages and its results are:

Hence, from the above table,
We can observe that the ages of Jasmine and James are the same
Hence, from the above,
We can conclude that for any type of the whole number, the ages of Jasmine and James are the same

Essential Question
Will a one-variable equation always have only one solution?
Answer:
Every linear equation that is a conditional equation has one solution. However, not every linear equation in one variable has a single solution. There are two other cases: no solution and the solution set of all real numbers

Try It!

How many solutions does the equation
3x + 15 = 2x + 10 + x + 5 have?
The equation has ______ solutions.
3x + 15 = 2x + 10 + x + 5
3x + 15 = _____ x + ______
3x – _____ + 15 = 3x – _____ + 15
______ = _______
Answer:
The given equation is:
3x + 15 = 2x + 10 + x + 5
So,
3x + 15 = 3x + 15
Subtract with 3x on both sides
So,
15 = 15
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

Convince Me!
If the value of x is negative, would the equation still be true? Explain.
Answer:
For the given equation,
3x + 15 = 2x + 10 + x + 5,
The solutions are infinite i..e, for any value of x, the given equation will be true i.e., for both positive and negative values of x, the equation will be true
Hence, from the above,
We can conclude that the given equation would still be true even if the value of x is negative

Try It!

How many solutions does the equation 4x + 8 = 0.1x + 3 + 3.9x have? Explain.
Answer:
The given equation is:
4x + 8 = 0.1x + 3 + 3.9x
So,
4x + 8 = 4x + 3
Subtract with 4x on both sides
So,
8 = 3
Hence, from the above,
We can conclude that the given equation has no solutions

Try It!

Determine the number of solutions each equation has without solving. Explain your reasoning.
a. 3x + 1.5 = 2.5x + 4.7
Answer:
The give equation is:
3x + 1.5 = 2.5x + 4.7
Rearrange the like terms
So,
3x – 2.5x = 4.7 – 1.5
0.5x = 3.2
Divide by 0.5 into both sides
So,
x = \(\frac{3.2}{0.5}\)
x = 6.4
Hence, from the above,
We can conclude that the given equation ahs only 1 solution

b. 3(x + 2) = 3x – 6
Answer:
The given equation is:
3 (x + 2) = 3x – 6
So,
3 (x) + 3 (2) = 3x – 6
3x + 6 = 3x – 6
Subtract with 3x on both sides
So,
6 = -6
Hence, from the above,
We can conclude that the given equation has no solutions

c. 9x – 4 = 5x – 4 + 4x
Answer:
The given equation is:
9x – 4 = 5x – 4 + 4x
So,
9x – 4 = 9x – 4
Subtract with 9x on both sides
So,
-4 = -4
4 = 4
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

KEY CONCEPT

A one-variable equation has infinitely many solutions when solving results in a true statement, such as 2 = 2.
A one-variable equation has one solution when solving results in one value for the variable, such as x = 2.
A one-variable equation has no solution when solving results in an untrue statement, such as 2 = 3.

Do You Understand?
Question 1.
Essential Question Will a one-variable equation always have only one solution?
Answer:
Every linear equation that is a conditional equation has one solution. However, not every linear equation in one variable has a single solution. There are two other cases: no solution and the solution set of all real numbers

Question 2.
Use Structure Kaylee writes the equation 6x + 12 = 2(3x + 6). Can you find the number of solutions this equation has without solving for x? Explain.
Answer:
The given equation is:
6x + 12 = 2 (3x + 6)
So,
6x + 2 = 2 (3x) + 2 (6)
6x + 12 = 6x + 12
Subtract with 12 on both sides
So,
12 = 12
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

Question 3.
Construct Arguments The height of an experimental plant after x days can be represented by the formula 3(4x + 2). The height of a second plant can be represented by the formula 6(2x + 2). Is it possible that the two plants will ever be the same height? Explain.
Answer:
It is given that
The height of an experimental plant after x days can be represented by the formula 3(4x + 2). The height of a second plant can be represented by the formula 6(2x + 2)
So,
Now,
To find out whether the two plants will ever be the same height or not,
3 (4x + 2) = 6 (2x + 2)
So,
3 (4x) + 3 (2) = 6 (2x) + 6 (2)
12x + 6 = 12x + 12
Subtract with 12x on both sides
So,
6 = 12
So,
The given equation has no solution
Hence, from the above,
We can conclude that it is not possible the two plants will ever be the same height

Do You Know How?
Question 4.
How many solutions does the equation 3(2.4x + 4) = 4.1x + 7 + 3.1x have? Explain.
Answer:
The given equation is:
3 (2.4x + 4) = 4.1x + 7 + 3.1x
So,
3 (2.4x) + 3 (4) = 7.2x + 7
7.2x + 12 = 7.2x + 7
Subtract with 7.2x on both sides
So,
12 = 7
Hence, from the above,
We can conclude that the given equation has no solutions

Question 5.
How many solutions does the equation 7x + 3x – 8 = 2(5x – 4) have? Explain.
Answer:
The given equation is:
7x + 3x – 8 = 2 (5x – 4)
So,
10x – 8 = 2 (5x) – 2 (4)
10x – 8 = 10x – 8
Subtract with 10x on both sides
So,
-8 = -8
8 = 8
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

Question 6.
Todd and Agnes are making desserts. Todd buys peaches and a carton of vanilla yogurt. Agnes buys apples and a jar of honey. They bought the same number of pieces of fruit. Is there a situation in which they pay the same amount for their purchases? Explain.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 30
Answer:
It is given that
Todd and Agnes are making desserts. Todd buys peaches and a carton of vanilla yogurt. Agnes buys apples and a jar of honey. They bought the same number of pieces of fruit.
Now,
Let the number of pieces of fruit be x
So,
The amount purchased by Todd = $1.25x + $4
The amount purchased by Agnes = $1x + $6
Now,
To find whether they pay the same amount for purchase or not,
$1.25x + $4 = $1x + $6
Rearrange the like terms
So,
$1.25x – $1x = $6 – $4
$0.25x = $2
Divide by 0.25 into both sides
So,
x = \(\frac{2}{0.25}\)
x = 8
Hence, from the above,
We can conclude that if there are 8 fruits, then Todd and Agnes will pay the same amount for purchase

Practice & Problem Solving

Leveled Practice In 7 and 8, complete the equations to find the number of solutions.
Question 7.
Classify the equation 33x + 99 = 33x – 99 as having one solution, no solution, or infinitely many solutions.
33x + 99 = 33x – 99
33x – ______ + 99 = 33x – _____ – 99
99 ______ – 99
Since 99 is _______ equal to -99, the equation has _______ solution(s).
Answer:
The given equation is:
33x + 99 = 33x – 99
Subtract with 33x on both sides
So,
33x – 33x + 99 = 33x – 33x – 99
99 = -99
We know that,
99 ≠ -99
Hence, from the above,
We can conclude that there are no solutions for the given equation

Question 8.
Solve 4(4x + 3) = 19x + 9 – 3x + 3. Does the equation have one solution, no solution, or infinitely many solutions?
4(4x + 3) = 19x + 9 – 3x + 3
4 • ______ + 4 • ______ = 19x + 9 – 3x + 3
16x + 12 = _______ + _______
16x – ______ + 12 = 16x ______ + 12
12 _______ 12
Since 12 is ________ equal to 12, the equation has ________ solution(s).
Answer:
The given equation is:
4 (4x + 3) = 19x + 9 – 3x + 3
So,
4 (4x) + 4 (3) = 16x + 12
16x + 12 = 16x + 12
Subtract with 16x on both sides
So,
16x – 16x + 12 = 16x – 16x + 12
12 = 12
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

Question 9.
Generalize What does it mean if an equation is equivalent to 0 = 0? Explain.
Answer:
If an equation is equivalent to 0 = 0, then
The equation is true for all the values of x
Hence,
That equation has infinitely many solutions

Question 10.
Solve 4x + x + 4 = 8x – 3x + 4. Does the equation have one solution, no solution, or infinitely many solutions? If one solution, write the solution. Explain.
Answer:
The given equation is:
4x + x + 4 = 8x – 3x + 4
So,
5x + 4 = 5x + 4
Subtract with x on both sides
So,
5x – 5x + 4 = 5x – 5x + 4
4 = 4
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

Question 11.
Reasoning Two rival dry cleaners both advertise their prices. Let x equal the number of items dry cleaned. Store A’s prices are represented by the expression 15x – 2. Store B’s prices are represented by the expression 3(5x + 7). When do the two stores charge the same rate? Explain.
Answer:
It  is given that
Two rival dry cleaners both advertise their prices. Let x equal the number of items dry cleaned. Store A’s prices are represented by the expression 15x – 2. Store B’s prices are represented by the expression 3(5x + 7)
So,
To find when the two stores charge the same rate,
15x – 2 = 3 (5x + 7)
So,
15x – 2 = 3 (5x) + 3 (7)
15x – 2 = 15x – 21
Subtract with 15x on both sides
So,
15x – 15x – 2 = 15x – 15x – 21
-2 = -21
2 = 21
So,
The equation has no solution
Hence, from the above,
We can conclude that the two stores will never charge the same rate

Question 12.
Reasoning How is solving an equation with no solution similar to solving an equation that has an infinite number of solutions?
Answer:
No solution would mean that there is no answer to the equation. It is impossible for the equation to be true no matter what value we assign to the variable. Infinite solutions would mean that any value for the variable would make the equation true.

Question 13.
Solve 0.9x + 5.1x – 7 = 2(2.5x – 3). How many solutions does the equation have?
Answer:
The given equation is:
0.9x + 5.1x – 7 = 2 (2.5x – 3)
So,
6.0x – 7 = 2 (2.5x) – 2 (3)
6x – 7 = 5x – 6
Rearrange the like terms
So,
6x – 5x = 7 – 6
x = 1
Hence, from the above,
We can conclude that the given equation has only 1 solution

Question 14.
Critique Reasoning Your friend solved the equation 4x + 12x – 6 = 4(4x + 7) and got x = 34.
What error did your friend make? What is the correct solution?
4x + 12x – 6 = 4 (4x + 7).
16x – 6 = 16x + 28
16x – 16x – 6 = 16x – 16x + 28
x – 6= 28
x – 6 + 6 = 28 + 6
x = 34
Answer:
The given equation is:
4x + 12x – 6 = 4 (4x + 7)
So,
16x – 6 = 4 (4x) + 4 (7)
16x – 6 = 16x + 28
Subtract with 16x on both sides
So,
16x – 16x – 6 = 16x – 16x + 28
-6 = 28
So,
From the above,
We can observe that after subtracting the given equation with 16x, there are no x terms.
So,
We can’t get the value of x but your friend takes variable x after subtracting 16x from the given equation even though there is no possibility for the x-term
Hence, from the above,
We can conclude that the correct solution for the given equation is: No solutions for the given equation

Question 15.
Solve 49x + 9 = 49x + 83.
a. Does the equation have one solution, no solution, or infinitely many solutions?
Answer:
The given equation is:
49x + 9 = 49x + 83
Subtract with 49x on both sides
So,
49x – 49x + 9 = 49x – 49x + 83
9 = 83
Hence, from the above,
We can conclude that the given equation has no solutions

b. Write two equations in one variable that have the same number of solutions as this equation.
Answer:
The two equations in one variable that have the same number of solutions as the equation that is present in part (a) are:
A) 10x + 8 = 10x – 25
B) 5 (3x + 10) = 15x + 40

Question 16.
Classify the equation 6(x + 2) = 5(x + 7) as having one solution, no solution, or infinitely many solutions.
Answer:
The given equation is:
6 (x + 2) = 5 (x + 7)
So,
6 (x) + 6 (2) = 5 (x) + 5 (7)
6x + 12 = 5x + 35
Rearrange the like terms
So,
6x – 5x = 35 – 12
x = 23
Hence, from the above,
We can conclude that the given equation has only 1 solution

Question 17.
Solve 6x + 14x + 5 = 5(4x + 1). Write a word problem that this equation, or any of its equivalent forms, represents.
Answer:
The given equation is:
6x + 14x + 5 = 5 (4x + 1)
So,
20x + 5 = 5 (4x) + 5 (1)
20x + 5 = 20x + 5
Subtract with 20x on both sides
So,
20x – 20x + 5 = 20x – 20x + 5
5 = 5
Hence, from the above,
We can conclude that the given equation is true for any value of x i..e, the given equation has infinitely many solutions

Question 18.
Classify the equation 170x – 1,000 = 30(5x – 30) as having one solution, no solution, or infinitely many solutions.
Answer:
The given equation is:
170x – 1,000 = 30 (5x – 30)
So,
170x – 1,000 = 30 (5x) – 30 (30)
170x – 1,000 = 150x – 900
Rearrange the like terms
So,
170x – 150x = 1,000 – 900
20x = 100
x= \(\frac{100}{20}\)
x = 5
Hence, from the above,
We can conclude that the given equation has only 1 solution

Question 19.
Higher Order Thinking Write one equation that has one solution, one equation that has no solution, and one equation that has infinitely many solutions.
Answer:
The example representation of the equation that has one solution is:
20x + 5 = 15x – 4
The example representation of the equation that has no solutions is:
3 (6x – 2) = 9 (2x – 4)
The example representation of the equation that has infinitely many solutions is:
4 (2x – 6) = 8 (x – 3)

Question 20.
Solve 4(4x – 2) + 1 = 16x – 7.
Answer:
The given equation is:
4 (4x – 2) + 1 = 16x – 7
So,
4 (4x) – 4 (2) + 1 = 16x – 7
16x – 8 + 1 = 16x – 7
16x – 7 = 16x – 7
Subtract with 16x on both sides
So,
16x – 16x – 7 = 16x – 16x – 7
-7 = -7
7 = 7
Hence, from the above,
We can conclude that the given equation is true for all the values of x i..e, the given equation has infinitely many solutions

Question 21.
Solve 6x + 26x – 10 = 8(4x + 10).
Answer:
The given equation is:
6x + 26x – 10 = 8 (4x + 10)
So,
32x – 10 = 8 (4x) + 8 (10)
32x – 10 = 32x + 80
Subtract with 32x on both sides
So,
32x – 32x – 10 = 32x – 32x + 80
-10 = 80
Hence, from the above,
We can conclude that the given equation has no solution

Question 22.
Classify the equation 64x – 16 = 16(4x – 1) as having one solution, no solution, or infinitely many solutions.
Answer:
The given equation is:
64x – 16 = 16 (4x – 1)
So,
64x – 16 = 16 (4x) – 16 (1)
64x – 16 = 64x – 16
Subtract with 64x on both sides
So,
64x – 64x – 16 = 64x – 64x – 16
– 16 = -16
16 = 16
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

Question 23.
Classify the equation 5(2x + 3) = 3(3x + 12) as having one solution, no solution, or infinitely many solutions.
Answer:
The given equation is:
5 (2x + 3) = 3 (3x + 12)
So,
5 (2x) + 5 (3) = 3 (3x) + 3 (12)
10x + 15 = 9x + 36
Rearrange the like terms
So,
10x – 9x = 36 – 15
x = 21
Hence, from the above,
We can conclude that the given equation has only 1 solution

Assessment Practice
Question 24.
Which of the following best describes the solution to the equation 4(2x + 3) = 16x + 12 – 8x?
A. The equation has one solution.
B. The equation has infinitely many solutions.
C. The equation has no solution.
D. The equation has two solutions.
Answer:
The given equation is:
4 (2x + 3) = 16x + 12 – 8x
So,
4 (2x) + 4 (3) = 4x + 12
8x + 12 = 4x + 12
Rearrange the like terms
So,
8x – 4x = 12 – 12
4x = 0
x = 0
So,
The given equation has only 1 solution
Hence, from the above,
We can conclude that option A matches with the solution of the given equation

Question 25.
Which of the following statements are true about the equation 10x + 45x – 13 = 11(5x + 6)? Select all that apply.
☐ The operations that can be used to solve the equation are addition and multiplication.
☐ The operations that can be used to solve the equation are multiplication and division.
☐ The equation has infinitely many solutions.
☐ The equation has a solution of x = 53.
☐ The equation has no solution.
Answer:
Let the given options be named: A, B, C, D, and E
Now,
The given equation is:
10x + 45x – 13 = 11 (5x + 6)
So,
55x – 13 = 11 (5x) + 11 (6)
55x – 13 = 55x + 66
Subtract with 55x on both sides
So,
55x – 55x – 13 = 55x – 55x + 66
-13 = 26
Hence, from the above,
We can conclude that option A and option E matches with the situation for the given equation

Topic 2 MID-TOPIC CHECKPOINT

Question 1.
Vocabulary How can you determine the number of solutions for an equation? Lesson 2-4
Answer:
A one-variable equation has infinitely many solutions when solving results in a true statement, such as 2 = 2.
A one-variable equation has one solution when solving results in one value for the variable, such as x = 2.
A one-variable equation has no solution when solving results in an untrue statement, such as 2 = 3.

Question 2.
Solve the equation –\(\frac{2}{3}\)d – \(\frac{1}{4}\)d = -22 for d. Lesson 2-1
Answer:
The given equation is:
–\(\frac{2}{3}\)d – \(\frac{1}{4}\)d = -22
So,
\(\frac{8 + 3}{12}\)d = 22
\(\frac{11}{12}\)d = 22
Multiply with \(\frac{12}{11}\) on both sides
So,
d = 22 × \(\frac{12}{11}\)
d = \(\frac{22 × 12}{11}\)
d = 24
Hence, from the above,
We can conclude that the value of d is: 24

Question 3.
Edy has $450 in her savings account. She deposits $40 each month. Juan has $975 in his checking account. He writes a check for $45.45 each month for his cell phone bill. He also writes a check for $19.55 each month for his water bill. After how many months will Edy and Juan have the same amount of money in their accounts? Lesson 2-2
Answer:
It is given that
Edy has $450 in her savings account. She deposits $40 each month. Juan has $975 in his checking account. He writes a check for $45.45 each month for his cell phone bill. He also writes a check for $19.55 each month for his water bill.
Now,
Let the number of months be x
So,
The amount of money in the account of Edy = $450 + $40x
The amount of money in the account of Juan = $975 – $45.45x – $19.55x
Now,
To find after how many months they will have the same amount of money in their accounts,
$450 + $40x = $975 – $45.45x – $19.55x
$450 + $40x = $975 – $65x
Rearrange the like terms
So,
$65x + $40x = $975 – $450
$105x = $525
Divide by 105 into both sides
So,
x = \(\frac{$25}{105}\)
x = 5 months
Hence, from the above,
We can conclude that after 5 months, Edy and Jian will have the same amount of money in their accounts

Question 4.
Which equation has infinitely many solutions? Lesson 2-4
A. \(\frac{3}{4}\)x + x – 5 = 10 + 2x
Answer:
The given equation is:
\(\frac{3}{4}\)x + x – 5 = 10 + 2x
\(\frac{3 + 4}{4}\)x – 5 = 10 + 2x
\(\frac{7}{4}\)x – 5 = 10 + 2x
Rearrange the like terms
So,
\(\frac{7}{4}\)x – 2x = 10 + 5
–\(\frac{1}{4}\)x = 15
Multiply with -4 on both sides
So,
x = -60
Hence, from the above,
We acn conclude that the given equation has only 1 solution

B. 3x – 2.7 = 2x + 2.7 + x
Answer:
The given equation is:
3x – 2.7 = 2x + x + 2.7
3x – 2.7 = 3x + 2.7
Subtract with 3x on both sides
So,
-2.7 = 2.7
Hence, from the above,
We can conclude that the given equation has no solutions

C. 9x + 4.5 – 2x = 2.3 +7x + 2.2
Answer:
The given equation is:
9x + 4.5 – 2x = 2.3 + 7x + 2.2
7x + 4.5 = 7x + 4.5
Subtract with 7x on both sides
So,
4.5 = 4.5
Hence, from the above,
We can conclude that the given equation has infinitely many solutions

D. \(\frac{1}{5}\) x – 7 = \(\frac{3}{4}\) + 2x – 25\(\frac{3}{4}\)
Answer:
The given equation is:
\(\frac{1}{5}\) x – 7 = \(\frac{3}{4}\) + 2x – 25\(\frac{3}{4}\)
We know that,
25\(\frac{3}{4}\) = \(\frac{103}{4}\)
So,
\(\frac{1}{5}\) x – 7 = \(\frac{3}{4}\) + 2x – \(\frac{103}{4}\)
Rearrange the like terms
So,
\(\frac{1}{5}\)x – 2x = 7 – \(\frac{103}{4}\)
–\(\frac{9}{5}\)x = –\(\frac{75}{4}\)
Multiply with –\(\frac{5}{9}\) on both sides
So,
x = \(\frac{75 × 5}{4 × 9}\)
x = \(\frac{125}{4}\)
Hence, from the above,
We can conclude that the given equation has only 1 solution

Question 5.
Solve the equation -4(x – 1) + 6x = 2(17 – x) for x. Lesson 2.3
Answer:
The given equation is:
-4 (x – 1) + 6x = 2 (17 – x)
So,
-4 (x) + 4 (1) + 6x = 2 (17) – 2 (x)
-4x + 4 + 6x = 34 – 2x
2x + 4 = 34 – 2x
Rearrange the like terms
So,
2x + 2x = 34 – 4
4x = 30
Divide by 4 on both sides
So,
x = \(\frac{30}{4}\)
x = \(\frac{15}{2}\)
Hence, from the above,
We can conclude that the value of x is: \(\frac{15}{2}\)

Question 6.
Hakeem subtracted 8 from a number, then multiplied the difference by \(\frac{4}{5}\). The result was 20. Write and solve an equation to find the number, x. Lesson 2-3
Answer:
It is given that
Hakeem subtracted 8 from a number, then multiplied the difference by \(\frac{4}{5}\). The result was 20.
Now,
Let the number be x
So,
According to Hakeem,
The expression that represents the given situation is:
\(\frac{4}{5}\) (x – 8) = 20
Multiply with \(\frac{5}{4}\) on both sides
So,
x – 8 = \(\frac{5 × 20}{4}\)
x – 8 = 25
Add with 8 on both sides
So,
x = 25 + 8
x = 34
Hence, from the baove,
We can conclude that Hakeem’s number is: 34

Topic 2 MID-TOPIC PERFORMANCE TASK

Hector is competing in a 42-mile bicycle race. He has already completed 18 miles of the race and is traveling at a constant speed of 12 miles per hour when Wanda starts the race. Wanda is traveling at a constant speed of 16 miles per hour.

PART A
Write and solve an equation to find when Wanda will catch up to Hector.
Answer:
It is given that
Hector is competing in a 42-mile bicycle race. He has already completed 18 miles of the race and is traveling at a constant speed of 12 miles per hour when Wanda starts the race. Wanda is traveling at a constant speed of 16 miles per hour.
Now,
Let the time be x
We know that,
Speed = \(\frac{Distance} {Time}\)
So,
Time = \(\frac{Distance}{Speed}\)
Now,
Time taken by Hector to complete a bicycle race = \(\frac{42 – 18}{12}\)
x = \(\frac{24}{12}\)
x = 2 hours
Now,
Time taken by Wanda to complete the bicycle race = \(\frac{The total distance of race}{The speed traveled by Wanda}\)
x = \(\frac{42}{16}\)
x = \(\frac{21}{8}\) hours
x = 2.625 hours
Now,
The time that took Wanda to catch up to Hector = The time taken by Wanda to complete the race – The tie taken by Hector to complete the race
= 2.625 – 2
= 0.625
= 0.625 (60 minutes)
= 37.5 minutes
Hence, from the above,
We can conclude that Wanda will catch up to Hector after 37.5 minutes of Hector completing the race

PART B
Will Wanda catch up to Hector before the race is complete? Explain.
Answer:
From part (a),
The time taken by Hector to complete the race is: 2 hours
The time taken by Wanda to complete the race is: 2.625 hours
So,
From the above times,
We can observe that the race is completed at 2 hours
Hence, from the above,
We can conclude that Wanda can’t catch up to Hector before the race is complete

PART C
At what constant speed could Wanda travel to catch up with Hector at the finish line? Explain.
Answer:
We know that,
Speed = \(\frac{Distance}{Time}\)
So,
The speed at which Wanda travel to catch up to Hector = \(\frac{The distance of the race}{The time taken by Hector to complete the race}\)
= \(\frac{42}{2}\)
= 21 miles per hour
Hence, from the above,
We can conclude that at 21 miles per hour speed, Wanda could catch up to Hector

3-Act Mathematical Modeling: Powering Down

3-ACT MATH
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.1

АСТ 1

Question 1.
After watching the video, what is the first question that comes to mind?
Answer:
After watching the video,
The first question that comes to mind is:
what will be the battery percentage you should have to complete your work?

Question 2.
Write the Main Question you will answer.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.2
Answer:
The main question you will answer is:
what will be the battery percentage you should have to complete your work?

Question 3.
Construct Arguments Predict an answer to this Main Question. Explain your prediction.
Answer:
The answer to the main question is: 100%
Reason for the prediction:
We don’t know how much work has left. So, it is better to have a battery percentage of 100%

Question 4.
On the number line below, write a time that is too early to be the answer. Write a time that is too late.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.3
Answer:
The time that is too early to be the answer for the above problem is: 5 minutes
The time that is too late to be the answer for the above problem is: Greater than the time that battery percentage is 100%

Question 5.
Plot your prediction on the same number line.

ACT 2

Question 6.
What information in this situation would be helpful to know? How would you use that information?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.4
Answer:
The information in this situation that would be helpful to know is:
A) The time is taken for battery percentage to be full

Question 7.
Use Appropriate Tools What tools can you use to solve the problem? Explain how you would use them strategically.
Answer:

Question 8.
Model with Math
Represent the situation using mathematics. Use your representation to answer the Main Question.
Answer:

Question 9.
What is your answer to the Main Question? Is it earlier or later than your prediction? Explain why.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.5
Answer:

ACT 3

Question 10.
Write the answer you saw in the video.
Answer:

Question 11.
Reasoning Does your answer match the answer in the video? If not, what are some reasons that would explain the difference?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.6
Answer:

Question 12.
Make Sense and Persevere Would you change your model now that you know the answer? Explain.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.7
Answer:

Act 3

Reflect

Question 13.
Model with Math
Explain how you used a mathematical model to represent the situation. How did the model help you answer the Main Question?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.8
Answer:

Question 14.
Look for Relationships What pattern did you notice in the situation? How did you use that pattern?
Answer:

SEQUEL

Question 15.
Be Precise After 35 minutes, he started charging his phone. 21 minutes later, the battery is at 23%. Explain how you would determine when the phone will be charged to 100%.
Answer:

Lesson 2.5 Compare Proportional Relationships

Solve & Discuss It!

Mei Li is going apple picking. She is choosing between two places. The cost of a crate of apples at each place is shown.
Where should Mei Li go to pick her apples? Explain.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 150.9
Answer:
It is given that Mei Li is going apple picking. She is choosing between two places.
So,
In Annie’s Apple Orchard,
The cost of 20lb of apples is: $7.25
In Franklin’s fruit Orchard,
The cost of 12lb of apples is: $5
We know that,
Where the cost of 1lb of apples is low, Mei Li will go there to buy the apples
Now,
In Annie’s Apple Orchard,
The cost of 1lb of apples = \(\frac{$7.25}{20}\)
= $0.3625
In Franklin’s fruit Orchard,
The cost of 1lb of apples = \(\frac{$5}{12}\)
= $0.4166
So,
The cost of 1lb of apples in Annie’s Orchard < The cost f 1lb of apples in Franklin’s fruit Orchard
Hence, from the above,
We can conclude that Mei Li should go to pick apples from Annie’s Apple Orchard

Construct Arguments
What information provided can be used to support your answer?
Answer:
From the given figure,
The information provided that can be used to support your answer is:
The weight of the apples is inversely proportional to the price of the apples
So,
In Annie’s Apple Orchard, the weight of the apples is high when compared to the weight of the apples in franklin’s fruit Orchard
Hence,
The price of the apples is low in Annie’s Apple Orchard when compared to Franklin’s fruit Orchard

Focus on math practices
Model with Math Which representation did you use to compare prices? Explain why.
Answer:
The relation that is used to compare the prices of apples is:
Weight of the apples ∝ \(\frac{1}{Price of the apples}\)

? Essential Question
How can you compare proportional relationships represented in different ways?
Answer:
To compare proportional relationships represented in different ways, find the unit rate, or the constant of proportionality, for each representation.

Try It!
The graph represents the rate at which Marlo makes origami birds for a craft fair. The equation y = 2.5x represents the number of birds, y, Josh makes in x minutes. Who makes birds at a faster rate?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.1
Answer:
It is given that
The graph represents the rate at which Marlo makes origami birds for a craft fair. The equation y = 2.5x represents the number of birds, y, Josh makes in x minutes.
So,
The rate that birds made by Josh = \(\frac{y}{x}\)
= 2.5
Now,
From the graph,
The rate that birds made by Marlo = \(\frac{Time taken to make birds by Marlo}{The number of birds}\)
= \(\frac{40}{8}\) (Here, we can take any value that is present in the graph. For example,\(\frac{20}{4}\), \(\frac{10}{2}\) etc., )
= 5
So,
The rate that birds made by Marlo > The rate that birds made by Josh
Hence, from the above,
We can conclude that Marlo makes birds at a faster rate

Convince Me!
If you were to graph the data for Josh and Marlo on the same coordinate plane, how would the two lines compare?
Answer:
When we graph the data for Josh and Marlo on the same coordinate plane,
We can observe that the two graphs will be the lines that are parallel to each other and the rate of change  of Marlo will be greater than the rate of change of Josh

Try It!
The distance covered by the fastest high-speed train in Japan traveling at maximum speed is represented on the graph. The fastest high-speed train in the United States traveling at maximum speed covers 600 kilometers in 2\(\frac{1}{2}\) hours. Which train has a greater maximum speed? Explain.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.2
Answer:
It is given that
The distance covered by the fastest high-speed train in Japan traveling at maximum speed is represented on the graph. The fastest high-speed train in the United States traveling at maximum speed covers 600 kilometers in 2\(\frac{1}{2}\) hours.
Now,
We know that,
Speed = \(\frac{Distance}{Time}\)
So,
The speed of the fastest high-speed train in the United states = 600 / \(\frac{5}{2}\)
We know that,
2\(\frac{1}{2}\) = \(\frac{5}{2}\)
So,
The speed of the fastest high-speed train in the United states = \(\frac{600 × 2}{5}\)
= 240 kilometers per hour
Now,
From the given graph,
The speed of the fastest high-speed train in Japan = \(\frac{The difference between any two distances from the graph}{The  difference between the values of the time that corresponds to the taken value of distances}\)
= \(\frac{1000 – 650}{3 – 2}\)
= 350 kilometers per hour
So,
The speed of the fastest high-speed train in Japan > The speed of the fastest high-speed train in the United States
Hence, from the above,
We can conclude that the fastest high-speed train in Japan has a maximum speed

KEY CONCEPT
To compare proportional relationships represented in different ways, find the unit rate, or the constant of proportionality, for each representation.
The representations below show the rental cost per hour for canoes at three different shops.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.3

Do You Understand?

Question 1.
?Essential Question How can you compare proportional relationships represented in different ways?
Answer:
To compare proportional relationships represented in different ways, find the unit rate, or the constant of proportionality, for each representation.

Question 2.
How can you find the unit rate or constant of proportionality for a relationship represented in a graph?
Answer:
In a graph,
The unit rate or constant of proportionality for a relationship is represented by:
\(\frac{The value of y}{The value of x}\) or \(\frac{The difference between any 2 values of y}{The difference between the values of x that is corresponded to the values of x}\)

Question 3.
Generalize Why can you use the constant of proportionality with any representation?
Answer:
We can use the constant of proportionality to find the rate of change between the physical quantities that have a proportional relationship
Ex:
Speed Vs Distance, Speed Vs Time, etc

Do You Know How?

Question 4.
Amanda babysits and Petra does yard work on weekends. The graph relating Amanda’s earnings to the number of hours she babysits passes through the points (0, 0) and (4, 24). The table below relates Petra’s earnings to the number of hours she does yard work.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.4
Who earns more per hour?
Answer:
It is given that
Amanda babysits and Petra does yard work on weekends. The graph relating Amanda’s earnings to the number of hours she babysits passes through the points (0, 0) and (4, 24). The table below relates Petra’s earnings to the number of hours she does yard work.
Now,
The Earnings per hour of Amanda = \(\frac{24 – 0}{4 – 0}\)
= \(\frac{24}{4}\)
= 6
The Earnings per hour of Petra = \(\frac{15}{3}\)
= 5
So,
The Earnings per hour of Amanda > The Earnings per hour of Petra
Hence, from the above,
We can conclude that Amanda earns more

Question 5.
Milo pays $3 per pound for dog food at Pat’s Pet Palace. The graph below represents the cost per pound of food at Mark’s Mutt Market. At which store will Milo pay a lower price per pound for dog food?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.5
Answer:
It is given that
Milo pays $3 per pound for dog food at Pat’s Pet Palace. The graph below represents the cost per pound of food at Mark’s Mutt Market.
So,
Now,
The cost per pound of food at Mark’s Mutt Market = \(\frac{Any value of cost from the given graph}{The value of weight that corresponds to the selected cost}\)
= \(\frac{5}{1}\)
= $5
So,
The cost per pound of food at Pat’s Pet Palace < The cost per pound of food at Mark’s Mutt Market
Hence, from the above,
We can conclude that at Pat’s Pet Palace, Milo will pay a lower price per pound for dog food

Practice & Problem Solving

Leveled Practice For 6 and 7, complete the information to compare the rates.

Question 6.
Sam and Bobby want to know who cycled faster. The table shows the total miles Sam traveled over time. The graph shows the same relationship for Bobby. Who cycled faster.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.6
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.67
Find the unit rate (constant of proportionality) for Bobby.
Use (Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.7) and (Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.7) to find the constant of proportionality.
The unit rate (constant of proportionality) is Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.8
So Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.10 cycled faster.
Answer:
It is given that
Sam and Bobby want to know who cycled faster. The table shows the total miles Sam traveled over time. The graph shows the same relationship for Bobby.
We know that,
Speed = \(\frac{Distance}{Time}\)
So,
For Sam, from the table,
Speed = \(\frac{20}{2}\) miles per hour
= 10 miles per hour
Now,
For Bobby, from the graph,
Speed = \(\frac{Any value of the distance from the graph}{The value of time that corresponds to the distance that we have taken}\)
= \(\frac{72}{8}\)
= 9 miles per hour
So,
The speed of Sam > The speed of Bobby
Hence, from the above,
We can conclude that Sam cycled faster

Question 7.
Model with Math The equation y = 15x can be used to determine the amount of money, y, Pauli’s Pizzeria makes by selling x pizzas. The graph shows the money Leo’s Pizzeria takes in for different numbers of pizzas sold. Which pizzeria makes more money per pizza?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.100
Pauli’s Pizzeria takes in Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.11 per pizza.
Leo’s Pizzeria takes in Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.11 per pizza.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.11‘s Pizzeria takes in more money per pizza.
Answer:
It is given that
The equation y = 15x can be used to determine the amount of money, y, Pauli’s Pizzeria makes by selling x pizzas. The graph shows the money Leo’s Pizzeria takes in for different numbers of pizzas sold
So,
The money earned by Pauli’s Pizzeria = \(\frac{y}{x}\)
= 15 (From the given equation y = 15x)
Now,
From the given graph,
The money earned by Leo’s Pizzeria = \(\frac{Any value of the amount made from the graph}{The value of pizzas sold that corresponds to the value of the amount that we have considered}\)
= \(\frac{96}{8}\)
= 12
So,
The money earned by Pauli’s Pizzeria > The money earned by Leo’s Pizzeria
Hence, from the above,
We can conclude that Pauli’s Pizzeria takes in more money per pizza

Question 8.
The graph shows the amount of savings over time in Eliana’s account. Lana, meanwhile, puts $50 each week into her savings account. If they both begin with $0, who is saving at the greater rate?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.12
Answer:
It is given that
The graph shows the amount of savings over time in Eliana’s account. Lana, meanwhile, puts $50 each week into her savings account
So,
The amount of savings over time in Lana’s account = \(\frac{Any value of total savings in the graph}{The corresponding value of time to that savings amount}\)
= \(\frac{94}{2}\)
= $47
So,
The amount of savings over time in Elina’s account > The amount of savings over time in Lana’s account
Hence, from the above,
We can conclude that Elina is saving money at a greater rate

Question 9.
Make Sense and Persevere Beth, Manuel, and Petra are collecting sponsors for a walk-a-thon. The equation y = 20x represents the amount of money Beth raises for walking x miles. The table shows the relationship between the number of miles Manuel walks and the amount of money he will raise. Petra will earn $15 for each mile that she walks.
a. In order to compare the proportional relationships, what quantities should you use to find the unit rate?
Answer:
In order to compare the proportional relationships,
The quantities you should use to find the unit rate is:
A) The number of miles walked
B) The amount of money raised for the corresponding number of miles

b. Compare the amount of money raised per mile by the three people.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.13
Answer:
It is given that
Beth, Manuel, and Petra are collecting sponsors for a walk-a-thon. The equation y = 20x represents the amount of money Beth raises for walking x miles. The table shows the relationship between the number of miles Manuel walks and the amount of money he will raise. Petra will earn $15 for each mile that she walks.
So,
The amount of money raised by Beth = \(\frac{y}{x}\)
= $20 (From the equation y = 20x)
Now,
The amount of money raised by Manuel = \(\frac{Any value of the money raised in the table}{The number of miles walked that corresponds to the value of money raised}\)
= \(\frac{$45}{3}\)
= $15
So,
The amount of money raised by Beth > The amount of money raised by Manuel = The amount of money raised by Petra
Hence, from the above,
We can conclude that Beth raised more amount of money when compared to Manuel and Petra

Question 10.
Higher-Order Thinking Winston compares the heights of two plants to see which plant grows more per day. The table shows the height of Plant 1, in centimeters, over 5 days. The graph shows the height of Plant 2, in centimeters, over 10 days. Winston says that since Plant 1 grows 6 cm per day and Plant 2 grows 4 cm per day, Plant 1 grows more per day.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.14
a. Do you agree with Winston? Explain your response.
Answer:
It is given that
Winston compares the heights of two plants to see which plant grows more per day. The table shows the height of Plant 1, in centimeters, over 5 days. The graph shows the height of Plant 2, in centimeters, over 10 days. Winston says that since Plant 1 grows 6 cm per day and Plant 2 grows 4 cm per day, Plant 1 grows more per day.
So,
From the given information,
The height growth of plant 1 > The height growth of plant 2
Hence, from the above,
You can agree with Winston

b. What errors might Winston have made?
Answer:
For plant 1,
The height growth per day = \(\frac{Any value of height}{The value of days correspond to the value of height}\)
= \(\frac{6}{2}\)
= 3 cm
For plant 2,
The height growth per day = \(\frac{Any value of height}{The value of days correspond to the value of height}\)
= \(\frac{4}{2}\)
= 2 cm
But,
It is given that
Winston says that Plant 1 grows 6 cm per day and Plant 2 grows 4 cm per day
But according to the calculation,
Plant 1 grows 3 cm per day and plant 2 grows 2 cm per day
So,
The calculation of the height growth of the plants are the errors made by Winston

Assessment Practice

Question 11.
Ashton, Alexa, and Clara want to know who types the fastest. The equation y = 39x models the rate at which Ashton can type, where y is the number of words typed and x is the time in minutes. The table shows the relationship between words typed and minutes for Alexa. The graph shows the same relationship for Clara. Who types the fastest?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.15
Answer:
It is given that
Ashton, Alexa, and Clara want to know who types the fastest. The equation y = 39x models the rate at which Ashton can type, where y is the number of words typed and x is the time in minutes. The table shows the relationship between words typed and minutes for Alexa. The graph shows the same relationship for Clara.
So,
The rate at which Ashton can type = \(\frac{y}{x}\)
= 39 words per minute (From the equation y = 39x)
The rate at which Alexa can type = \(\frac{Any value of the words typed from the table}{The value of minds corresponds to the words typed}\)
= \(\frac{78}{2}\)
= 39 words per minute
The rate at which Clara can type = \(\frac{Any value of the words typed from the graph}{The value of minds corresponds to the words typed}\)
= \(\frac{78}{2}\)
= 39 words per minute
So,
The rate at which Ashton can type = The rate at which Alexa can type = the rate at which Clara can type
Hence, from the above,
We can conclude that no one is the fastest

Lesson 2.6 Connect Proportional Relationships and Slope

ACTIVITY

Solve & Discuss It!

In the fall, Rashida earns money as a soccer referee for her town’s under-10 soccer league. So far, she has worked 5 games and has been paid $98.50. She will work a total of 14 games this fall. How can Rashida determine how much she will earn refereeing soccer games this fall?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.20
Answer:
It is given that
In the fall, Rashida earns money as a soccer referee for her town’s under-10 soccer league. So far, she has worked 5 games and has been paid $98.50. She will work a total of 14 games this fall.
So,
The amount of money paid for 1 game = \(\frac{The amount of money paid for 5 games}{5}\)
= \(\frac{$98.50}{5}\)
= $19.70
So,
The amount of money paid for 14 games to Rashida = (The total number of games) × (The amount of money paid for 1 game)
= 14 × $19.70
= $275.80
Hence, from the above,
We can conclude that by finding out the money paid to a game for Rashida, Rashida can find total money earned by refereeing soccer games in the fall

Look for Relationships
How is the number of games Rashida works related to her earnings?
Answer:
From the above,
We can observe that Rashida earns more money by refereeing more soccer games
Hence, from the above,
We can conclude that
The number of games Rashida works ∝ The earnings of Rashida

Focus on math practices
Reasoning: How would Rashida’s earnings change if she were paid by the hour instead of by the game?
Answer:
Rashida’s earnings would increase if she were paid by the hour instead of by the game
Example:
From the above,
We can observe that
The money earned by Rashida per game = $17.90
But, if a game will continue for 2 hours and the amount of money that is per game will also be applicable to this situation, then
The amount of money earned by Rashida for this game = $17.90 × 2 = $35.80
Hence, from the above,
We can conclude that Rashida can earn more if she were paid by the hour instead of by the game

? Essential Question
What is the slope?
Answer:
The slope of a line is a measure of its steepness. Mathematically, the slope is calculated as “rise over run” (change in y divided by change in x).
The representation of the slope mathematically is:
Slope = \(\frac{Rise}{Run}\)

Try It!

Jack graphs how far he plans to bike over a 3-day charity ride. Find the slope of the line.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.21
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.22
Answer:
It is given that Jack graphs how far he plans to bike over a 3-day charity ride
Now,
From the given graph,
The given points are: (3, 90), and (2, 60)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y2  – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{60 – 90}{2 – 3}\)
= 30
Hence, from the above,
We can conclude that the slope of the line is: 30

Convince Me!
How do the unit rate and constant of proportionality relate to the slope of a line?
Answer:
The relative steepness of the line is called slope. The slope of a graph is the same as the constant of proportionality of the equation. A line with a steeper slope has a larger value for k.

Try It!
The graph shows the proportions of red and blue food coloring that Taylor mixes to make the purple frosting. What is the slope of the line? Tell what it means in the problem situation.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.23
Answer:
It is given that
The graph shows the proportions of red and blue food coloring that Taylor mixes to make the purple frosting.
Now,
From the given graph,
The given points are: (50, 70), and (25, 35)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y2  – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{70 – 35}{50 – 25}\)
= \(\frac{35}{25}\)
= \(\frac{7}{5}\)
Hence, from the above,
We can conclude that
For every 7 parts of red food coloring, we have to mix 5 parts of blue food coloring to make the purple frosting

KEY CONCEPT

Slope is the measure of the steepness of a line. It represents the ratio of the rise (that is, the vertical distance) to the run (the horizontal distance) between two points on the line. In proportional relationships, slope is the same as the unit rate and constant of proportionality.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.24
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 160.25

Do You Understand?

Question 1.
? Essential Question
What is the slope?
Answer:
The slope of a line is a measure of its steepness. Mathematically, the slope is calculated as “rise over run” (change in y divided by change in x).
The representation of the slope mathematically is:
Slope = \(\frac{y2  – y1}{x2 – x1}\) (or) Sloe = \(\frac{Rise}{Run}\)

Question 2.
Reasoning How is the slope related to a unit rate?
Answer:
The slope is the unit rate, which is the coefficient of x. For a table, the change in y divided by the change in x is the unit rate or slope.

Question 3.
Look for Relationships Why is the slope between any two points on a straight line always the same?
Answer:
The ratio of the rise over run describes the slope of all straight lines. This ratio is constant between any two points along a straight line, which means that the slope of a straight line is constant, too, no matter where it is measured along the line.

Do You Know How?

Question 4.
What is the slope of the line?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.1
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.1
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{ Any value of y}{The value of x that corresponds to the taken value of y}\)
= \(\frac{Price ($)}{Grapes (lb)}\)
So,
The slope of the line = \(\frac{6}{2}\)
= 3
Hence, from the above,
We can conclude that the slope of the line is: 3

Question 5.
The scale of a model airplane is shown in the graph.
a. Find the slope of the line using \(\frac{y2  – y1}{x2 – x1}\)
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.2
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.2
Now,
From the given graph,
The given points are: (6, 10), and (3, 5)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y2  – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{5 – 10}{3 – 6}\)
= \(\frac{5}{3}\)
Hence, from the above,
We can conclude that the slope of the line is: \(\frac{5}{3}\)

b. What does the slope mean in the problem situation?
Answer:
From part (a),
The slope is: \(\frac{5}{3}\)
So,
From the above slope,
We can conclude that for every 3 cm, the model airplane can fly 5 feet

Practice & Problem Solving

Leveled Practice in 6 and 7, find the slope of each line.

Question 6.
The graph shows the number of soda bottles a machine can make over time. Use the two points shown to find the number of soda bottles the machine can make per minute.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.3
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.4
The machine Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.5 can make soda bottles each minute.
Answer:
It is given that
The graph shows the number of soda bottles a machine can make over time
Now,
The given graph is:
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.4
Now,
From the given graph,
The given points are: (6, 150), and (2, 50)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y2  – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{50 – 150}{2 – 6}\)
= \(\frac{100}{4}\)
= 25
Hence, from the above,
We can conclude that the machine can make 25 soda bottles each minute

Question 7.
Find the slope of the line.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.55
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.55
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{ Any value of y}{The value of x that corresponds to the taken value of y}\)
= \(\frac{Items}{Time in min}\)
So,
The slope of the line = \(\frac{50}{10}\)
= 5
Hence, from the above,
We can conclude that the slope of the line is: 5

Question 8.
Reasoning How can you find the slope of the line that passes through the points (0,0) and (2, 4)? Explain.
Answer:
The given points are: (0, 0), and (2, 4)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{4 – 0}{2 – 0}\)
= \(\frac{4}{2}\)
= 2
Hence, from the above,
We can conclude that the slope of the line is: 2

Question 9.
The points (2.1, -4.2) and (2.5, -5) form a proportional relationship. What is the slope of the line that passes through these two points?
Answer:
It is given that the points (2.1, -4.2) and (2.5, -5) form a proportional relationship
Now,
The given points are: (2.1, -4.2), and (2.5, -5)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{-5 + 4.2}{2.5 – 2.1}\)
= \(\frac{-0.8}{0.4}\)
= -2
Hence, from the above,
We can conclude that the slope of the line that passes through the given points is: -2

Question 10.
Find the slope of the line.
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.6
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.6
Now,
From the graph,
We can observe that
The given points are: (-3, 7), and (-1, 2)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{2 – 7}{-1 + 3}\)
= \(\frac{-5}{2}\)
= –\(\frac{5}{2}\)
Hence, from the above,
We can conclude that the slope of the line that passes through the given points is: –\(\frac{5}{2}\)

Question 11.
The graph shows the number of Calories Natalia burned while running.
a. What is the slope of the line?
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.7
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answer Key Topic 2 Analyze And Solve Linear Equations 180.7
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{ Any value of y}{The value of x that corresponds to the taken value of y}\)
= \(\frac{Calories}{Time in min}\)
So,
The slope of the line = \(\frac{70}{7}\)
= 10
Hence, from the above,
We can conclude that the slope of the line is: 10

b. What does the slope tell you?
Answer:
From part (a),
We can observe that
The slope of the line is: 10
So,
From the given slope,
We can conclude that Natalia burns 10 calories per minute while running

Question 12.
Critique Reasoning A question on a test provides this graph and asks students to find the speed at which the car travels. Anna incorrectly says that the speed of the car is \(\frac{1}{64}\) mile per hour.
a. What is the speed of the car?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.8
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.8
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{ Any value of y}{The value of x that corresponds to the taken value of y}\)
= \(\frac{Distance in miles}{Time in hours}\)
So,
The slope of the line = \(\frac{256}{4}\)
= 64
Hence, from the above,
We can conclude that the speed of the car is: 64 miles per hour

b. What error might Anna have made?
Answer:
From part (a),
We can observe that the speed of the car is: 64 miles per hour
Bt,
According to Anna,
The speed of the car is: \(\frac{1}{64}\) miles per hour
So,
The error made by Anna is that she takes the slope in the form of \(\frac{x}{y}\) but the actual form of the slope is \(\frac{y}{x}\)

Question 13.
Higher-Order Thinking You use a garden hose to fill a wading pool. If the water level rises 11 centimeters every 5 minutes and you record the data point of (10, y), what is the value of y? Use slope to justify your answer.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.9
Answer:
It is given that
You use a garden hose to fill a wading pool. If the water level rises 11 centimeters every 5 minutes and you record the data point of (10, y)
We know that,
Slope = \(\frac{Rise}{Run}\)
So,
From the given information,
We can write the slope as:
Slope = \(\frac{11}{5}\)
Now,
Compare the given point with (x, y)
So,
The slope of the line = \(\frac{y}{x}\)
= \(\frac{y}{10}\)
So,
\(\frac{y}{10}\) = \(\frac{11}{5}\)
Multiply with 10 on both sides
So,
y = \(\frac{11 × 10}{5}\)
y = 22
Hence, from the above,
We can conclude that the value of y is: 22

Assessment Practice

Question 14.
The points (15, 21) and (25, 35) form a proportional relationship.
a. Find the slope of the line that passes through these points.
Answer:
It is given that the points (15, 21) and (25, 35) form a proportional relationship.
Now,
The given points are: (15, 21), and (25, 35)
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope = \(\frac{Rise}{Run}\) = \(\frac{y – y1}{x2 – x1}\)
So,
The slope of the line = \(\frac{35 – 21}{25 – 15}\)
= \(\frac{14}{10}\)
= \(\frac{7}{5}\)
Hence, from the above,
We can conclude that the slope of the line that passes through the given points is: \(\frac{7}{5}\)

b. Which graph represents this relationship?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.10
Answer:
We know that,
The representation of the equation when two points form  a proportionate relationship is:
y = kx
and the line have to pass through the origin i.e., (0, 0)
So,
From the given graphs,
The graphs B and C have the possibility to become the graph of the given points
Now,
We know that,
Slope = \(\frac{Rise}{Run}\)
From graph B,
Slope = \(\frac{42}{30}\)
= \(\frac{7}{5}\)
From graph C,
Slope = \(\frac{30}{42}\)
= \(\frac{5}{7}\)
Hence, from the above,
We can conclude that the graph B represents the given relationship

Lesson 2.7 Analyze Linear Equations: y = mx

ACTIVITY

Explore It!

A group of college students developed a solar-powered car and entered it in a race. The car travels at a constant speed of 100 meters per 4 seconds.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.11
A. What representation can show the distance the car will travel over time?
Answer:
It is given that
A group of college students developed a solar-powered car and entered it in a race. The car travels at a constant speed of 100 meters per 4 seconds.
We know that,
Speed = \(\frac{Distance}{Time}\)
It is given that speed is constant
So,
Distance ∝ Time
So,
The greater the distance, the greater the time
Hence, from the above,
We can conclude that
The representation that can show the distance the car will travel over time is:
Distance ∝ Time

B. What expression can show the distance the car will travel over time?
Answer:
From part (a),
We can observe that
Distance ∝ Time (Since the speed is constant)
Hence,
The expression that can show the distance the car will travel over time is:
Distance = k (Time)
Where,
k is a constant

C. Compare the representation and the expression. Which shows the distance traveled over time more clearly? Explain.
Answer:
From part (a),
The representation that can show the distance traveled over time is:
Distance ∝ Time
The expression that can show the distance traveled over time is:
Distance = k (Time)
Now,
From the representation and the expression,
We can observe that the expression shows the distance traveled over time more clearly because for any value of distance and time, the value of the expression is constant
Hence, from the above,
We can conclude that the expression shows the distance traveled over time more clearly

Focus on math practices
Be Precise How would the representation or expression change if the speed was converted to miles per minute?
Answer:
From part (a),
The representation is:
Distance ∝ Time
The expression is:
Distance = k (Time)
Now,
Even if the speed was converted to miles per minute, there will be no change in the representation and the expression because miles per minute is a unit of speed and it won’t affect the overall situation of the representation and the expression

? Essential Question
How does slope relate to the equation for a proportional relationship?
Answer:
The steepness of the slope for directly proportional relationships increases as the value of the constant m (y = mx) increases.

Try It!
Write an equation to describe the relationship shown in the graph.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.12. The equation of the line is y = Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.13x.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.14
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.14
Now,
From the given graph,
The points are: (3, 60), and (4, 80) [We can take any 2 ordered pairs from the graph like (0, 0), and (1, 20); (2, 40), and (3, 60), etc]
Now,
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope can be represented as “m”
So,
m = \(\frac{y – y1}{x2 – x1}\)
So,
m = \(\frac{80 – 60}{4 – 3}\)
= \(\frac{20}{1}\)
= 20
We know that,
The equation of the line is:
y = mx
Hence, from the above,
We can conclude that
The equation of the line is: y = 20x

Convince Me!
How do the equations y = mx and y = kx compare?
Answer:
We can compare y = kx to the slope-intercept form of a line, y = mx + b. We can see that y = kx is a linear equation with slope k and y-intercept 0. This tells us that the graph of a direct variation is a line that passes through the origin, point (0,0).

Try It!
a. Write the equation of the line.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.15
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.15
Now,
From the given graph,
The points are: (10, 4), and (-10, -4)
Now,
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope can be represented as “m”
So,
m = \(\frac{y – y1}{x2 – x1}\)
So,
m = \(\frac{-4 – 4}{-10 – 10}\)
= \(\frac{-8}{-20}\)
= \(\frac{2}{5}\)
We know that,
The equation of the line is:
y = mx
So,
y = \(\frac{2}{5}\)x
Multiply with 5 on both sides
So,
5y = 2x
Hence, from the above,
We can conclude that
The equation of the line is: 5y = 2x

b. Graph the line y = -3x.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.16
Answer:
The given equation is:
y = -3x
Hence,
The representation of the given equation in the coordinate plane is:

KEY CONCEPT

The equation for a proportional relationship is y = mx where m represents the slope of the line.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 180.17

Do You Understand?

Question 1.
Essential Question How does slope relate to the equation for a proportional relationship?
Answer:
The steepness of the slope for directly proportional relationships increases as the value of the constant m (y = mx) increases.

Question 2.
Look for Relationships What do the graphs of lines in the form y = mx have in common? How might they differ?
Answer:
The graphs of lines in the form y = mx are all straight lines that pass through the origin

Question 3.
Use Structure The table below shows the distance a train traveled over time. How can you determine the equation that represents this relationship?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 181.2
Answer:
It is given that
The table below shows the distance a train traveled over time.
Now,
Verify whether \(\frac{Distance}{Time}\) is constant or not
Now,
From the given table,
For 25 m and 2s,
\(\frac{Distance}{Time}\) = \(\frac{25}{2}\)
For 50m and 4s,
\(\frac{Distance}{Time}\) = \(\frac{50}{4}\) = \(\frac{25}{2}\)
Since,
\(\frac{Distance}{Time}\) is constant
Speed is also constant
So,
The representation of the equation that describes the given relationship is:
Distance = k (Time)
So,
y = mx [ Compare the above equation with y = mx ]
Where
m is a constant slope
So,
y = \(\frac{25}{2}\)x
2y = 25x
Hence, from the above,
We can conclude that the representation of the equation that represents the given situation is: 2y = 25x

Do You Know How?

Question 4.
The relationship between a hiker’s elevation and time is shown in the graph.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 181.3
a. Find the constant of proportionality of the line. Then find the slope of the line.
Answer:
It is given that
The relationship between a hiker’s elevation and time is shown in the graph.
Now,
We know that,
The constant of proportionality and the slope are the same
So,
Slope of the line (m) = \(\frac{y}{x}\)
So,
From the given graph,
\(\frac{y}{x}\) = \(\frac{120}{4}\)
= 30
So,
m = 30
Hence, from the above,
We can conclude that the slope of the line is: 30

b. Write the equation of the line.
Answer:
We know that,
The equation of the line is:
y = mx
From part (a),
m = 30
Hence, from the above,
We can conclude that the equation of the line is: y = 30x

Question 5.
Graph the equation y = –\(\frac{1}{2}\)x.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 181.4
Answer:
The given equation is:
y = –\(\frac{1}{2}\)x
Hence,
The representation of the given equation in the coordinate plane is:

Practice & Problem Solving

Question 6.
Leveled Practice Resting heart rate is a measure of how fast the heart beats when a person is not performing physical activity. The graph shows the number of heartbeats over time for a given person.
a. Use two sets of coordinates to write an equation to describe the relationship.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 181.5
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 181.6
Answer:
It is given that
Resting heart rate is a measure of how fast the heart beats when a person is not performing physical activity. The graph shows the number of heartbeats over time for a given person.
Now,
From the given graph,
The points are: (3, 210), and (4, 280)
Now,
Compare the given points with (x1, y1), and (x2, y2)
We know that,
Slope can be represented as “m”
So,
m = \(\frac{y – y1}{x2 – x1}\)
So,
m = \(\frac{280 – 210}{4 – 3}\)
= \(\frac{70}{1}\)
= 70
We know that,
The equation of the line is:
y = mx
Hence, from the above,
We can conclude that
The equation of the line that describes the given situation is: y = 70x

b. Interpret the equation in words.
The heart’s resting heart rate is Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 182.1 beats each minute.
Answer:
From part (a),
The equation of the line that describes the given situation is: y = 70x
Hence, from the above,
We can conclude that the heart’s resting heart rate is 70 beats each minute

Question 7.
Model with Math The graph relates the number of gallons of white paint to the number of gallons of red paint Jess used to make the perfect pink. Write an equation that describes the relationship.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 182.10
Answer:
It is given that
The graph relates the number of gallons of white paint to the number of gallons of red paint Jess used to make the perfect pink.
Now,
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 182.10
Now,
Slope of the given line (m) = \(\frac{y}{x}\)
m = \(\frac{4}{1}\)
m = 4
We know that,
The equation of the line is:
y = mx
Hence, from the above,
We can conclude that the equation of the line that represents the given situation is: y = 4x

Question 8.
Critique Reasoning Franco made this graph to show the equation y = -x. Is the graph correct? Explain.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 182.100
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 182.100
Now,
We know that,
Slope of the line (m) = \(\frac{y}{x}\)
m = \(\frac{4}{4}\)
m = 1
We know that,
The equation of the line is:
y = mx
So,
The equation of the line is:
y = x
But,
Franco made this graph to show the equation y = -x
Hence, from the above,
We can conclude that the graph of Franco is not correct

Question 9.
The graph shows a proportional relationship between the variables x and y.
a. Write an equation to model the relationship.
b. Reasoning Explain how you know if an equation or a graph represents a proportional relationship.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.1
Answer:
a.
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.1
We know that,
The slope of the line (m) = \(\frac{y}{x}\)
= \(\frac{96}{8}\)
= 12
We know that,
The equation of the line is:
y = mx
So,
The equation of the line to the given relationship is:
y = 12x
Hence, from the above,
We can conclude that the equation of the line that represents the given situation is: y = 12x

b.
If the relationship between two quantities is a proportional relationship, this relationship can be represented by the graph of a straight line through the origin with a slope equal to the unit rate. For each point (x, y) on the graph, ž is equal to k, where k is the unit rate.

Question 10.
Model with Math Graph the equation y = -5x on the coordinate plane.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.50
Answer:
The given equation is:
y = -5x
Hence,
The representation of the given equation in the coordinate plane is:

Question 11.
Graph the equation y = \(\frac{3}{5}\)x on the coordinate plane.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.4
Answer:
The given equation is:
y = \(\frac{3}{5}\)x
Hence,
The representation of the given equation in the coordinate plane is:

Question 12.
Higher-Order Thinking A movie theater sends out a coupon for 70% off the price of a ticket.
a. Write an equation for the situation, where y is the price of the ticket with the coupon and x is the original price.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.5
Answer:
It is given that
A movie theater sends out a coupon for 70% off the price of a ticket.
So,
The proportionality constant of the given situation = \(\frac{70}{100}\)
= \(\frac{7}{10}\)
We know that,
Proportionality constant = Slope
So,
Slope (m) = \(\frac{7}{10}\)
We know that,
The equation of the line is:
y = mx
So,
y = \(\frac{7}{10}\)
10y = 7x
Hence, from the above,
We can conclude that the equation of the line for the given situation is: 10y = 7x

b. Graph the equation and explain why the line should only be in the first quadrant.
Answer:
From part (a),
The equation of the line is:
10y = 7x
So,
The representation of the given equation in the coordinate plane is:

From the graph,
We can observe that
The graph should only be in 1st quadrant because the values of x and y are both positive

Assessment Practice

Question 13.
An equation and a graph of proportional relationships are shown. Which has the greater unit rate? y = \(\frac{47}{2}\)x
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.6
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.6
From the given graph,
Slope (m) = \(\frac{y}{x}\)
= \(\frac{282}{6}\)
= 47
Now,
The given equation is:
y = \(\frac{47}{2}\)x
So,
Slope (m) = \(\frac{y}{x}\)
= \(\frac{47}{2}\)
Now,
When we compare the rates or slopes,
47 > \(\frac{47}{2}\)
Hence, from the above,
We ca conclude that the unit rate of the graph is greater than the unit rate of the equation

Question 14.
Car X travels 186 miles in 3 hours.
PART A Write the equation of the line that describes the relationship between distance and time.
Answer:
It is given that car X travels 186 miles in 3 hours.
Now,
We know that,
Speed = \(\frac{Distance}{Time}\)
We know that,
The equation of the line is:
y = mx
Where,
m = \(\frac{Distance}{Time}\)
So,
The equation of the line is:
y = \(\frac{186}{3}\)x
y = 62x
Hence, from the above,
We can conclude that the equation of the line that descries the relationship between distance and time is:
y = 62x

PART B Which graph represents the relationship between distance and time for Car X?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 183.7
Answer:
From part (a),
The equation of the line that describes the relationship between distance and time is:
y = 62x
Where,
62 —-> The value of \(\frac{y}{x}\) (or) m
So,
From the above graphs,
We can observe that,
m = 62 is possible from graphs C and D
But,
We know that,
The equation y = mx passes through the origin
Hence, from the above,
We can conclude that the graph C represents the relationship between distance and time for car X

Lesson 2.8 Understand the y-Intercept of a Line

Solve and Discuss It!

Eight-year-old Alex is learning to ride a horse. The trainer says that a horse ages 5 years for every 2 human years. The horse is now 50 years old in human years. How can you determine the age of the horse, in human years, when Alex was born?
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 184.1
Answer:
It is given that
Eight-year-old Alex is learning to ride a horse. The trainer says that a horse ages 5 years for every 2 human years. The horse is now 50 years old in human years.
So,
When Alex is 8 years old,
The age of the horse in human years is: 50 years
Now,
For every 2 human years, the horse ages 5 years
So,
So,
For Alex,
The number of times his age increases = \(\frac{8}{2}\)
= 4 times
So,
The increase in the age of the horse when Alex is 8 years old = 5 × 4 = 20 years
So,
The age of the horse when Alex born = The present age of the horse – The increased age of the horse
= 50 – 20
= 30 years
Hence, from the above,
We can conclude that the age of the horse when Alex is born is: 30 years

Focus on math practices
Use Structure A veterinarian says that cat ages 8 years for every 2 human years. If a cat is now 64 years old in cat years, how old is the cat in human years?
Answer:
It is given that
A veterinarian says that a cat ages 8 years for every 2 human years.
Now,
Let the age of the cat in human years be x
So,
\(\frac{The age of the cat in cat years}{The age of the cat in human years}\) = \(\frac{The increase of the age of the cat for the increase of human years}{The increase of the age of human for the increase of human years}\)
\(\frac{64}{x}\) = \(\frac{8}{2}\)
Divide by 64 into both sides
So,
\(\frac{64}{x × 64}\) = \(\frac{8}{2 × 64}\)
\(\frac{1}{x}\) = \(\frac{1}{16}\)
x = 16 years
Hence, from the above,
We can conclude that the age of cat in human years is: 16 years

? Essential Question
What is the y-intercept and what does it indicate?
Answer:
The slope and y-intercept values indicate characteristics of the relationship between the two variables x and y. The slope indicates the rate of change in y per unit change in x. The y-intercept indicates the y-value when the x-value is 0.

Try It!
Prices for a different bowling alley are shown in the graph. How much does this bowling alley charge for shoe rental? The line crosses the y-axis as Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 190.1
The y-intercept is Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 190.2
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 190.3
Answer:
It is given that
The prices for a different bowling alley are shown in the graph
So,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From the given graph,
The given line crosses the y-axis at (0, 3)
We know that,
The y-intercept is the value of y when the value of x is 0
Hence, from the above,
We can conclude that
The given passes through (0, 3)
The y-intercept is: 3

Convince Me!
In these examples, why does the y-intercept represent the cost to rent bowling shoes?
Answer:
In this example,
From the slope,
We can determine the cost of each game
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept and that y-intercept is the cost to rent bowling shoes because the cost won’t ever be zero

Try It!
What is the y-intercept of each graph? Explain.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 190.4
Answer:
Let the given graphs be named as graph A and graph B respectively
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From graph A,
The y-intercept is: (0, 2)
From graph B,
The y-intercept is: (0, -0.5)

KEY CONCEPT
The y-intercept is the y-coordinate of the point on a graph where the line crosses the y-axis.
When the line crosses through the origin, the y-intercept is 0.
When the line crosses above the origin, the y-intercept is positive.
When the line crosses below the origin, the y-intercept is negative.
Envision Math Common Core 8th Grade Answers Topic 2 Analyze And Solve Linear Equations 191.2

Do You Understand?

Question 1.
? Essential Question What is the y-intercept and what does it indicate?
Answer:
The slope and y-intercept values indicate characteristics of the relationship between the two variables x and y. The slope indicates the rate of change in y per unit change in x. The y-intercept indicates the y-value when the x-value is 0.

Question 2.
Look for Relationships Chelsea graphs a proportional relationship. Bradyn graphs a line that passes through the origin. What do you know about the y-intercept of each student’s graph? Explain your answer.
Answer:
It is given that
Chelsea graphs a proportional relationship. Bradyn graphs a line that passes through the origin
So,
From the given situation,
We can observe that
The graph of Chelsea may pass through the origin or may not pass through the origin i.e., the y-intercept may be zero, positive, or negative
The graph of Braydon passes through the origin i.e., the y-intercept is zero

Question 3.
Generalize When the y-intercept is positive, where does the line cross the y-axis on the graph? When it is negative?
Answer:
When the y-intercept is positive, the line crosses above the origin,
When the y-intercept is negative, the line crosses below the origin

Do You Know How?

Question 4.
What is the y-intercept shown in the graph?
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.5
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.5
From the given graph,
We can observe that the line passes through the origin
Hence, from the above,
We can conclude that the value of the y-intercept is: 0

Question 5.
The graph shows the relationship between the remaining time of a movie and the amount of time since Kelly hit “play.” What is the y-intercept of the graph and what does it represent?
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.8
Answer:
It is given that
The graph shows the relationship between the remaining time of a movie and the amount of time since Kelly hit “play.”
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From the graph,
We can observe that the line crosses the y-axis at (0, 1.8)
Hence, from the above,
We can conclude that the y-intercept of the graph is: 1.8
The y-intercept represents the remaining time of a movie in the given situation

Practice & Problem Solving

Question 6.
Leveled Practice Find the y-intercept of the line. The y-intercept is the point where the graph crosses the Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.9-axis.
The line crosses the y-axis at the point Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.10
The y-intercept is Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.9
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.100
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.100
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From the graph,
We can observe that
The line crosses the y-axis at the point (0, 7)
Hence, from the above,
We can conclude that
The y-intercept is the point where the graph crosses the y-axis
The y-intercept for the given graph is: 8

Question 7.
Find the y-intercept of the graph.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.99
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.99
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From the graph,
We can observe that
The line crosses the y-axis at the point (0, -4)
Hence, from the above,
We can conclude that
The y-intercept for the given graph is: -4

Question 8.
Find the y-intercept of the graph.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.101
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.101
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
Now,
From the graph,
We can observe that
The equation of the line is:
y = kx
From the above equation,
We can say that the line passes through the origin
So,
The line crosses the y-axis at the point (0, 0)
Hence, from the above,
We can conclude that
The y-intercept of the given graph is: 0

Question 9.
The graph represents the height y, in meters, of a hot air balloon x minutes after beginning to descend. How high was the balloon when it began its descent?
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.11
Answer:
It is given that
The graph represents the height y, in meters, of a hot air balloon x minutes after beginning to descend
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From the graph,
We can observe that the line crosses the y-axis at (0, 80)
The y-intercept of the graph gives us information about the height of the balloon when it began its descent
Hence, from the above,
We can conclude that the height of the balloon when it began its descent is: 80 m

Question 10.
Model with Math The graph represents the amount of gasoline in a canister after Joshua begins to fill it at a gas station pump. What is the y-intercept of the graph and what does it represent?
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.12
Answer:
It is given that
The graph represents the amount of gasoline in a canister after Joshua begins to fill it at a gas station pump.
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
Now,
From the graph,
We can observe that the line passes through the origin
So,
The line crosses the y-axis at the point (0, 0)
Hence, from the above,
We can conclude that
The y-intercept of the given graph is: 0
The y-intercept of the given graph represents the amount of gas in gallons at the starting time

Question 11.
The line models the temperature on a certain winter day since sunrise.
a. What is the y-intercept of the line?
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.13
Answer:
It is given that
The line models the temperature on a certain winter day since sunrise.
Now,
We know that,
y-coordinate of the point where the line crosses the y-axis is the y-intercept
So,
From the graph,
We can observe that the line crosses the y-axis at (0, 4)
Hence, from the above,
We can conclude that the y-intercept of the given line is: 4

b. What does the y-intercept represent?
Answer:
The y-intercept of the graph gives us information about the starting temperature on a certain winter day at sunrise

Question 12.
Higher-Order Thinking Your friend incorrectly makes this graph as an example of a line with a y-intercept of 3.
a. Explain your friend’s possible error.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.14
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.14
Now,
From the given graph,
We can observe that the line crosses the y-axis at: (0, 4)
So,
The y-intercept of the graph is: 4
But,
Your friend incorrectly makes this graph as an example of a line with a y-intercept of 3.
Hence, from the above,
We can conclude that the y-intercept of the given graph is 4 but not 3

b. Draw a line on the graph that does represent a y-intercept of 3.
Answer:
Let the equation with the y-intercept of 3 is:
y = x + 3
Hence,
The representation of the graph that does represent a y-intercept of 3 in the coordinate plane is:

Assessment Practice

Question 13.
For each graph, draw a line through the point such that the values of the x-intercept and y-intercept are additive inverses.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.15
Answer:
Let the graphs be named as graph A and graph B respectively
Now,
The given graphs are:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 192.15
So,
From graph A,
We can observe that the x-intercept is 3 and the y-intercept is 3
We know that,
The “Additive inverse” of a number ‘a’ is the number that, when added to ‘a’, yields zero. This number is also known as the opposite (number), sign change, and negation.
So,
The additive inverses of the x-intercept and y-intercept are: (-3, -3)
From graph B,
We can observe that the x-intercept is -3 and the y-intercept is -3
We know that,
The “Additive inverse” of a number ‘a’ is the number that, when added to ‘a’, yields zero. This number is also known as the opposite (number), sign change, and negation.
So,
The additive inverses of the x-intercept and y-intercept are: (3, 3)
Hence,
The representation of the additive inverses of the x and y-intercepts in the coordinate plane is:

Question 14.
Which statements describe the graph of a proportional relationship? Select all that apply.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 193.1 The y-intercept is always at the point (0, 1).
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 193.1 The line always crosses the y-axis at (0, 0).
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 193.1 The y-intercept is 0.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 193.1 The y-intercept is 1.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 193.1 The line does NOT cross the y-axis.
Answer:
Let the options be named as A, B, C, D, and E respectively
Now,
We know that,
The representation of the proportional relationship is:
y = kx
So,
From the equation,
We can say that the equation passes through the origin and the y-intercept is 0
Hence, from the above,
We can conclude that options B and C describes the proportional relationship

Lesson 2.9 Analyze Linear Equations: y = mx + b

ACTIVITY

Explain It!

Xiu and Jon take the tram from the base camp to the mountain summit. After about six and a half minutes in the tram, Jon says, “Cool! We are a mile above sea level.” Xiu says, “We passed the one-mile mark a couple of minutes ago.”
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 194.1

A. Construct an argument to defend Xiu’s statement.

B. What mistake could Jon have made? Explain.
Answer:

Focus on math practices
Reasoning Can you use the equation y = mx to represent the path of the tram? Is there a proportional relationship between x and y? Explain.

? Essential Question
What is the equation of a line for a nonproportional relationship?
Answer:
Linear equations can be written in the form y = mx + b. When b ≠ 0, the relationship between x and y is nonproportional.

Try It!
Write a linear equation in slope-intercept form for the graph shown.
The y-intercept of the line is Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 195.1
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 195.2
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 195.3
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 195.3
From the given graph,
We can observe that,
The points are: (8, 8), and (4, 5)
Compare the given points with (x1, y1), (x2, y2)
We know that,
The y-intercept of the line is the point that crosses the y-axis
So,
From the given graph,
The y-intercept is: 2
We know that,
The linear equation in the slope-intercept form is:
y = mx + c
Where,
m is the slope
c is the y-intercept
Now,
m = \(\frac{y2 – y1}{x2 – x1}\)
= \(\frac{5 – 8}{4 – 8}\)
= \(\frac{3}{4}\)
So,
The linear equation in the slope-intercept form is:
y = \(\frac{3}{4}\)x + 2
y = \(\frac{3x + 8}{4}\)
4y = 3x + 8
Hence, from the above,
We can conclude that the linear equation in the slope-intercept form is:
4y = 3x + 8

Convince Me!

What two values do you need to know to write an equation of a line, and how are they used to represent a line?
Answer:
To write an equation of a line in the slope-intercept form,
The two values you need to know are:
A) Slope of a line and it is represented as “m”
B) The y-intercept of a line and is represented as “c”

KEY CONCEPT

The equation of a line that represents a nonproportional relationship can be written in slope-intercept form, y = mx + b, where m is the slope of the line and b is the y-intercept.

Do You Understand?

Question 1.
? Essential Question What is the equation of a line for a nonproportional relationship?
Answer:
Linear equations can be written in the form y = mx + b. When b ≠ 0, the relationship between x and y is nonproportional.

Question 2.
Use Structure The donations by a restaurant to a certain charity, y, will be two-fifths of its profits, x, plus $50. How can you determine the equation in slope-intercept form that shows the relationship between x and y without graphing the line?
Answer:
It is given that
The donations by a restaurant to a certain charity, y, will be two-fifths of its profits, x, plus $50.
So,
Donations to a certain charity by a restaurant = The part of the profits of a restaurant + $50
y = \(\frac{2}{5}\)x + $50
Compare the above equation with
y = mx + c
Where,
m is the slope of a line
c is the y-intercept of a line
So,
When we compare the equation,
The slope of a line is (m): \(\frac{2}{5}\)
The y-intercept of a line is (c) : $50

Question 3.
Be Precise Priya will graph a line with the equation y = \(\frac{3}{4}\)x – 4. She wants to know what the line will look like before she graphs the line. Describe the line Priya will draw, including the quadrants the line will pass through.
Answer:
It is given that
Priya will graph a line with the equation y = \(\frac{3}{4}\)x – 4. She wants to know what the line will look like before she graphs the line.
Now,
Compare the given equation with
y = mx + c
Where,
m is the slope of the line
c is the y-intercept
So,
By comparing,
We get,
m = \(\frac{3}{4}\)
c = -4
Now,
From the y-intercept,
We can say that the y-intercept lies below the origin i.e., in the 3rd quadrant
From the slope of the line,
We can say that the value of m lies in the 1st quadrant
Hence, from the above,
We can conclude that the line drawn by Priya will be in the 4th quadrant for the above values of c and m

Do You Know How?

Question 4.
Chrissie says the equation of the line shown on the graph is y = \(\frac{1}{2}\)x – 5. George says that the equation of the line is y = \(\frac{1}{2}\)x + 5. Which student is correct? Explain.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.1
Answer:
It is given that
Chrissie says the equation of the line shown on the graph is y = \(\frac{1}{2}\)x – 5. George says that the equation of the line is y = \(\frac{1}{2}\)x + 5.
Now,
The given graph is
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.1
From the given graph,
The y-intercept is: 5
Now,
When we observe the given two equations,
The slope is the same and the y-intercepts are different and the correct y-intercept must be 5
Hence, from the above,
We can conclude that George is correct

Question 5.
Fara wants to rent a tent for an outdoor celebration. The cost of the tent is $500 per hour, plus an additional $100 set-up fee.
a. Draw a line to show the relationship between the number of hours the tent is rented, x, and the total cost of the tent, y.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.2
Answer:
It is given that
Fara wants to rent a tent for an outdoor celebration. The cost of the tent is $500 per hour, plus an additional $100 set-up fee.
Now,
The total cost of the rent = The cost of the rent per hour + Additional set-up fee
So,
y = 500x + 100
Hence,
The representation of the above equation in the coordinate plane is:

b. What is the equation of the line in slope-intercept form?
Answer:
We know that,
The total cost of the rent = The cost of the rent per hour + Additional set-up fee
So,
y = 500x + 100
Where,
x is the number of hours
The above equation is in the form of
y = mx + c
Which is the slope-intercept form of the equation
Hence, from the above,
We can conclude that the equation of the line in the slope-intercept form is:
y = 500x + 100

Practice & Problem Solving

Question 6.
Leveled Practice What is the graph of the equation y = 2x + 4?
The y-intercept is Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.3, which means the line crosses the y-axis at the point (Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 194). Plot this point.
The slope of the line is positive, so it goes Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.3 from left to right.
Start at the y-intercept. Move up Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.3, and then move right Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.3
You are now at the point (Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 194). Plot this point. Draw a line to connect the two points.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.5
Answer:
The given equation is:
y = 2x + 4
So,
The representation of the given equation in the coordinate plane is:

Compare the given equation with
y = mx + c
Wher,
m is the slope of a line
c is the y-intercept of a line
So,
The y-intercept of the given graph is 4 which means the line crosses the y-axis at the point (0, 4)
The slope of the line is positive, so it goes up from left to right.
Start at the y-intercept. Move up 2 units, and then move right 2 units
So,
You are now at the point (3, 10).

Question 7.
Write an equation for the line in slope-intercept form.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.6
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.6
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Now,
From the given graph,
We can observe that the y-intercept is: -3
Now,
The given points from the graph to find the slope are: (-2, -2), and (4, -5)
Now,
SLope (m) = \(\frac{-5  – (-2)}{4 – (-2)}\)
m = \(\frac{-3}{6}\)
m = –\(\frac{1}{2}\)
So,
The equation of the line in the slope-intercept form is:
y = –\(\frac{1}{2}\)x – 3
Hence, from the above,
We can conclude that the equation of the line in the slope-intercept form is:
y = –\(\frac{1}{2}\)x – 3

Question 8.
Write an equation for the line in slope-intercept form.
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.7
Answer:
The given graph is:
Envision Math Common Core Grade 8 Answers Topic 2 Analyze And Solve Linear Equations 199.7
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Now,
From the given graph,
We can observe that the y-intercept is: 4
Now,
The given points from the graph to find the slope are: (1, 1), and (0, 4)
Now,
SLope (m) = \(\frac{4 – 1}{0 – 1}\)
m = \(\frac{3}{-1}\)
m = -3
So,
The equation of the line in the slope-intercept form is:
y = -3x + 4
Hence, from the above,
We can conclude that the equation of the line in the slope-intercept form is:
y = -3x + 4

Question 9.
The line models the cost of renting a kayak. Write an equation in slope-intercept form for the line, where x is the number of hours the kayak is rented and y is the total cost of renting the kayak.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.8
Answer:
It is given that
The line models the cost of renting a kayak
where,
x is the number of hours the kayak is rented and y is the total cost of renting the kayak.
Nw,
The given graph is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.8
From the given graph,
We can observe that
The y-intercept of the graph is: 5
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Where,
m is the slope
c is the y-intercept
Now,
From the given graph,
The points to find the graph are: (3, 40), and (2, 30)
So,
Slope (m) = \(\frac{30 – 40}{2 – 3}\)
= 10
So,
The equation of the line in the slope-intercept form is:
y = mx + c
So,
y = 10x + 5
Hence, from the above,
We can conclude that
The equation of the line in the slope-intercept form is:
y = 10x + 5

Question 10.
Graph the equation y = 3x – 5.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.9
Answer:
The given equation is:
y = 3x – 5
Hence,
The representation of the given equation in the coordinate plane is:

Question 11.
Amy began with $25 in her bank account and spent $5 each day. The line shows the amount of money in her bank account. She incorrectly wrote an equation for the line in slope-intercept form as y = -5x + 5.
a. What is the correct equation for the line in slope-intercept form?
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.10
Answer:
It is given that
Amy began with $25 in her bank account and spent $5 each day. The line shows the amount of money in her bank account
Now,
The given graph is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.10
From the given graph,
The y-intercept is: 25
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Now,
The given points to find the slope are: (5, 0), and (1, 20)
So,
Slope (m) = \(\frac{20 – 0}{5 – 1}\)
= \(\frac{20}{5}\)
= 4
So,
The equation of the line in the slope-intercept form is:
y = 4x + 25
Hence, from the above,
We can conclude that the equation of the line in the slope-intercept form is:
y = 4x + 25

b. Critique Reasoning What mistake might Amy have made?
Answer:
Answer:
The mistakes might made by Amy are:
A) The value of y-intercept is 25 and the value of x-intercept is: 5
B) The slope is not negative as it moves down from top to bottom

Question 12.
Higher-Order Thinking The line represents the cost of ordering concert tickets online.
a. Write an equation for the line in slope-intercept form, where x is the number of tickets and y is the total cost.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.11
Answer:
It is given that
The line represents the cost of ordering concert tickets online.
Now,
The given graph is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 199.11
From the given graph,
The y-intercept is: 10
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Now,
The given points to find the slope are: (1, 33.25), and (0, 12.25)
So,
Slope (m) = \(\frac{12.25 – 33.25}{0 – 1}\)
= \(\frac{21}{1}\)
= 21
So,
The equation of the line in the slope-intercept form is:
y = 21x + 10
Hence, from the above,
We can conclude that the equation of the line in the slope-intercept form is:
y = 21x + 10

b. Explain how you can write an equation for this situation without using a graph.
Answer:
We know that,
The total cost of ordering concert tickets online = (The cost of 1 Ticket) × (The number of Tickets) + Processing fee
Let the number of tickets be x
Let the total cost of ordering concert tickets online be y
So,
y = 21x + 10
Hence, from the above,
We can conclude that the equation for this situation without using a graph is:
y = 21x + 10

c. Is this graph a good representation of the situation? Explain.
Answer:
Yes,
The given graph is good for the given situation because the equation of the line is the same for this situation with using the graph and without using the graph

Assessment Practice

Question 13.
What should you do first to graph the equation y = \(\frac{2}{5}\)x – 1?
A. Plot the point (0, 0).
B. Plot the point (2, 5).
C. Plot a point at the x-intercept.
D. Plot a point at the y-intercept.
Answer:
The given equation is:
y = \(\frac{2}{5}\)x – 1
Compare the above equation with
y = mx + c
Hence, from the above,
We can conclude that the first step to draw the graph for the given equation is:
Plot a point at the y-intercept

Question 14.
Write an equation for the line in slope-intercept form.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 200
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 200
From the given graph,
We can observe that
The y-intercept of the graph is: 8
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Where,
m is the slope
c is the y-intercept
Now,
From the given graph,
The points to find the graph are: (4, 0), and (0, 8)
So,
Slope (m) = \(\frac{8 – 0}{0 – 4}\)
= -2
So,
The equation of the line in the slope-intercept form is:
y = mx + c
So,
y = -2x + 8
Hence, from the above,
We can conclude that
The equation of the line in the slope-intercept form is:
y = -2x + 8

TOPIC 2 REVIEW

? Topic Essential Question

How can you analyze connections between linear equations and use them to solve problems?
Answer:
Assuming that your two equations are distinct (neither is merely a multiple of the other), we can use the “elimination by addition and subtraction” method or substitution method to eliminate one variable, leaving us with an equation in one variable, solve this 1-variable (Ex: in x) equation, and then use the resulting value in the other

Vocabulary Review

Complete each definition and provide an example of each vocabulary word.

Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 200.1

Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 200.12

Question 1.
The change in y divided by the change in x is the ____
Answer:
The change in y divided by the change in x is defined as the “Slope of a line”
Example:
Slope = \(\frac{y}{x}\)
= \(\frac{2}{5}\)

Question 2.
The point on the graph where the line crosses the y-axis is the ____ of a line.
Answer:
The point on the graph where the line crosses the y-axis is the “y-intercept” of a line. In the y-intercept, the value of x is 0
Example:
The point on the graph where the line crosses the y-axis is at (0, 2)
So,
The y-intercept is: 2

Question 3.
The ____ of a line is y = mx + b. The variable m in the equation stands for the __. The variable b in the equation stands for the ___
Answer:
The “Slope-intercept form” of a line is
y = mx + b
The variable m in the equation stands for the x-intercept.
The variable b in the equation stands for the y-intercept

Use Vocabulary in Writing
Paddle boats rent for a fee of $25, plus an additional $12 per hour. What equation, in y = mx + b form, represents the cost to rent a paddle boat for x hours? Explain how you write the equation. Use vocabulary words in your explanation.
Answer:
It is given that
Paddleboats rent for a fee of $25, plus an additional $12 per hour.
Where,
x represents the cost to rent a paddleboat for x hours
Now,
The total cost to rent a paddleboat = The cost of a paddleboat per hour + $12
y = $25x + $12
Hence, from the above,
We can conclude that the equation of the line for this situation is:
y = $25x + $12

Concepts and Skills Review

LESSON 2.1 Combine Like Terms to Solve Equations

Quick Review
You can use variables to represent unknown quantities. To solve an equation, collect like terms to get one variable on one side of the equation. Then use inverse operations and properties of equality to solve the equation.

Practice
Solve each equation for x.

Question 1.
2x + 6x = 1,000
Answer:
The given equation is:
2x + 6x = 1,000
So,
8x = 1,000
Divide by 8 into both sides
x = \(\frac{1,000}{8}\)
x = 125
Hence, from the above,
We can conclude that the value of x is: 125

Question 2.
2\(\frac{1}{4}\)x + 2\(\frac{1}{2}\)x = 44
Answer:
The given equation is:
2\(\frac{1}{4}\)x + 2\(\frac{1}{2}\)x = 44
We know that,
2\(\frac{1}{4}\) = \(\frac{9}{4}\)
2\(\frac{1}{2}\) = \(\frac{5}{2}\)
So,
\(\frac{9}{4}\)x + \(\frac{5}{2}\)x = 44
\(\frac{19}{4}\)x = 44
Multiply with \(\frac{4}{19}\) on both sides
So,
x = 44 × \(\frac{4}{19}\)
x = \(\frac{88}{19}\)
Hence, from the above,
We can conclude that the value of x is: \(\frac{88}{19}\)

Question 3.
-2.3x – 4.2x = -66.3
Answer:
The given equation is:
-2.3x – 4.2x = -66.3
So,
-6.5x = -66.3
6.5x = 66.3
Divide by 6.5 into both sides
So,
x = \(\frac{66.3}{6.5}\)
x = \(\frac{51}{5}\)
x = 10.2
Hence, from the above,
We can conclude that the value of x is: 10.2

Question 4.
Javier bought a microwave for $105. The cost was 30% off the original price. What was the price of the microwave before the sale?
Answer:
It is given that
Javier bought a microwave for $105. The cost was 30% off the original price
So,
The price of the microwave before the sale = The price of the microwave + 30% of the price of the microwave
= $105 + \(\frac{30}{100}\) ($105)
= $105 (\(\frac{130}{100}\))
= \(\frac{13650}{100}\)
= $136.5
Hence, from the above,
We can conclude that the price of the microwave before the sale is: $136.5

LESSON 2.2 Solve Equations with Variables on Both Sides

Quick Review
If two quantities represent equal amounts and have the same variables, you can set the expressions equal to each other. Collect all the variables on one side of the equation and all the constants on the other side. Then use inverse operations and properties of equality to solve the equation.

Practice
Solve each equation for x.

Question 1.
3x + 9x = 6x + 42
Answer:
The given equation is:
3x + 9x = 6x + 42
12x = 6x + 42
Rearrange the like terms
So,
12x – 6x = 42
6x = 42
So,
x = \(\frac{42}{6}\)
x = 7
Hence, from the above,
We can conclude that the value of x is: 7

Question 2.
\(\frac{4}{3}\)x + \(\frac{2}{3}\)x = \(\frac{1}{3}\)x + 5
Answer:
The given equation is:
\(\frac{4}{3}\)x + \(\frac{2}{3}\)x = \(\frac{1}{3}\)x + 5
So,
\(\frac{6}{3}\)x = \(\frac{1}{3}\)x + 5
\(\frac{6}{3}\)x – \(\frac{1}{3}[latex]x = 5
[latex]\frac{5}{3}\)x = 5
Multiply with \(\frac{3}{5}\) on both sides
So,
x = 5 × \(\frac{3}{5}\)
x = 3
Hence, from the above,
We can conclude that the value of x is: 3

Question 3.
9x – 5x + 18 = 2x + 34
Answer:
The given equation is:
9x – 5x + 18 = 2x + 34
So,
4x + 18 = 2x + 34
Rearrange the like terms
So,
4x – 2x = 34 – 18
2x = 16
Divide by 2 into both sides
So,
x = \(\frac{16}{2}\)
x = 8
Hence, from the above,
We can conclude that the value of x is: 8

Question 4.
Megan has $50 and saves $5.50 each week. Connor has $18.50 and saves $7.75 each week. After how many weeks will Megan and Connor have saved the same amount?
Answer:
It is given that
Megan has $50 and saves $5.50 each week. Connor has $18.50 and saves $7.75 each week.
Now,
Let x be the number of weeks
So,
The money saved by Megan = $50 + $5.50x
The money saved by Connor = $18.50 + $7.75x
So,
To find out after how many weeks Megan and Connor have saved the same amount,
$50 + $5.50x = $18.50 + $7.75x
Rearrange the like terms
So,
$50 – $18.50 = $7.75x – $5.50x
$31.05 = $2.25x
Divide by 2.25 into both sides
So,
x = \(\frac{31.05}{2.25}\)
x = 13.8
x = 14 weeks 1 day
x ≅ 14 weeks
Hence, from the above,
We can conclude that after approximately 14 weeks, Megan and Connor have saved the same amount

LESSON 2.3 Solve Multistep Equations

Quick Review
When solving multistep equations, sometimes the Distributive Property is used before you collect like terms. Sometimes like terms are collected, and then you use the Distributive Property.

Practice Solve each equation for x.

Question 1.
4(x + 4) + 2x = 52
Answer:
The given equation is:
4 (x + 4) + 2x = 52
So,
4 (x) + 4 (4) + 2x = 52
4x + 16 + 2x = 52
6x + 16 = 52
Rearrange the like terms
So,
6x = 52 – 16
6x = 36
x = \(\frac{36}{6}\)
x = 6
Hence, from the above,
We can conclude that the value of x is: 6

Question 2.
8(2x + 3x + 2) = -4x + 148
Answer:
The given equation is:
8 (2x + 3x + 2) = -4x + 148
So,
8 (5x + 2) = -4x + 148
8 (5x) + 8 (2) = -4x + 148
40x + 16 = -4x + 148
Rearrange the like terms
So,
40x + 4x = 148 – 16
44x = 132
x = \(\frac{132}{4}\)
x = 3
Hence, from the above,
We can conclude that the value of x is: 3

Question 3.
Justin bought a calculator and a binder that were both 15% off the original price. The original price of the binder was $6.20. Justin spent a total of $107.27. What was the original price of the calculator?
Answer:
It is given that
Justin bought a calculator and a binder that were both 15% off the original price. The original price of the binder was $6.20. Justin spent a total of $107.27.
So,
Total spent money of Justin = The original price of binder + The original price of a calculator
Let the original price of the calculator be x
So,
$6.20 + 30% of $6.20 + x + 30% of x = $107.27
$6.20 + \(\frac{3}{10}\) ($6.20) + x + \(\frac{3}{10}\) of x = $107.27
$6.20 + 1.86 + 1.3x = $107.27
$8.06 + 1.3x = $107.27
1.3x = $107.27 – $8.06
1.3x = 99.21
x = \(\frac{99.21}{1.3}\)
x = 76.31
Hence, from the above,
We can conclude that the original price of the calculator is: $76.31

LESSON 2.4 Equations with No Solutions or Infinitely Many Solutions

Quick Review
When solving an equation results in a statement that is always true, there are infinitely many solutions. When solving an equation produces a false statement, there are no solutions. When solving an equation gives one value for a variable, there is one solution.

Practice
How many solutions does each equation have?

Question 1.
x + 5.5 + 8 = 5x – 13.5 – 4x
Answer:
The given equation is:
x + 5.5 + 8 = 5x – 13.5 – 4x
So,
x + 13.5 = x – 13.5
Subtract with x on both sides
So,
13.5 = -13.5
Hence, from the above,
we can conclude that there are no solutions for the given equation

Question 2.
4(\(\frac{1}{2}\)x + 3) = 3x + 12 – x
Answer:
The given equation is:
4(\(\frac{1}{2}\)x + 3) = 3x + 12 – x
So,
4 × \(\frac{1}{2}\)x + 4 (3) = 3x + 12 – x
2x + 12 = 2x + 12
Subtract with 2x on both sides
So,
12 = 12
Hence, from the above,
We can conclude that there are infinitely many solutions for the given equation

Question 3.
2(6x + 9 – 3x) = 5x + 21
Answer:
The given equation is:
2 (6x + 9 – 3x) = 5x + 21
So,
2 (3x + 9) = 5x + 21
2 (3x) + 2 (9) = 5x + 21
6x + 18 = 5x + 21
Rearrange the like terms
So,
6x – 5x = 21 – 18
x = 3
Hence, from the above,
We can conclude that there is only 1 solution for the given equation

Question 4.
The weight of Abe’s dog can be found using the expression 2(x + 3), where x is the number of weeks. The weight of Karen’s dog can be found using the expression 3(x + 1), where x is the number of weeks. Will the dogs ever be the same weight? Explain.
Answer:
It is given that
The weight of Abe’s dog can be found using the expression 2(x + 3), where x is the number of weeks. The weight of Karen’s dog can be found using the expression 3(x + 1), where x is the number of weeks.
Now,
To find out whether the weight of the dogs will be the same or not,
2 (2x + 3) = 3 (3x + 1)
So,
2 (2x) + 2 (3) = 3 (3x) + 3 (1)
4x + 6 = 9x + 3
Rearrange the like terms
So,
9x – 4x = 6 – 3
5x = 3
x = \(\frac{3}{5}\)
So,
There is only 1 solution for the given equation
Hence, from the above,
We can conclude that the weights of the dogs will be the same

LESSON 2.5 Compare Proportional Relationships

Quick Review
To compare proportional relationships, compare the rate of change or find the unit rate.

Practice

Question 1.
Two trains are traveling at a constant rate. Find the rate of each train. Which train is traveling at the faster rate?
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 200.2
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 200.13
Answer:
We know that,
Unit rate = \(\frac{y}{x}\)
We know that,
Speed = \(\frac{Distance}{Time}\)
Now,
For Train A,
Unit rate = \(\frac{A value of Distance}{The value of time that corresponds to the Distance}\)
= \(\frac{50}{2}\)
= 25 miles per hour
For Train B,
Unit rate = \(\frac{y}{x}\)
= \(\frac{20}{1}\)
= 20 miles per hour
So,
Unit rate of Train A > Unit rate of Train B
Hence, from the above,
We can conclude that Train A is the fastest

Question 2.
A 16-ounce bottle of water from Store A. costs $1.28. The cost in dollars, y, of a bottle of water from Store B is represented by the equation y = 0.07x, where x is the number of ounces. What is the cost per ounce of water at each store? Which store’s bottle of water costs less per ounce?
Answer:
It is given that
A 16-ounce bottle of water from Store A. costs $1.28. The cost in dollars, y, of a bottle of water from Store B is represented by the equation y = 0.07x, where x is the number of ounces.
So,
The cost per ounce of water of store A = \(\frac{The cost of a 16-ounce bottle of water}{16}\)
= \(\frac{$1.28}{16}\)
= $0.08
The cost per ounce of water of store B = \(\frac{y}{x}\)
= $0.07
So,
The cost per ounce of water of store A > The cost per ounce of water of store B
Hence, from the above,
We can conclude that the cost per ounce of water of store B costs less per ounce

LESSON 2.6 Connect Proportional Relationships and Slope

Quick Review
The slope of a line in a proportional relationship is the same as the unit rate and the constant of proportionality.

Practice

Question 1.
The graph shows the proportions of blue paint and yellow paint that Briana mixes to make green paint. What is the slope of the line? Tell what it means in the problem situation.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 202.4
Answer:
It is given that
The graph shows the proportions of blue paint and yellow paint that Briana mixes to make green paint.
Now,
The given graph is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 202.4
So,
From the graph,
The slope of the given line = \(\frac{y}{x}\)
= \(\frac{5}{6}\)
Hence, from the above slope of the line,
We can conclude that for 5 parts of yellow paint, we have to mix 6 parts of blue paint to make green paint

LESSON 2.7 Analyze Linear Equations: y = mx

Quick Review
A proportional relationship can be represented by an equation in the form y = mx, where m is the slope.

Practice
A mixture of nuts contains 1 cup of walnuts for every 3 cups of peanuts.

Question 1.
Write a linear equation that represents the relationship between peanuts, x, and walnuts, y.
Answer:
It is given that
A mixture of nuts contains 1 cup of walnuts for every 3 cups of peanuts.
We know that,
Slope (m) = \(\frac{y}{x}\)
m = \(\frac{1}{3}\)
We know that,
The linear equation that represents the relationship between peanuts and walnuts is:
y = mx
So,
y = \(\frac{1}{3}\)x
x = 3y
Hence, from the above,
We can conclude that the linear equation that represents the relationship between peanuts and walnuts is:
x = 3y

Question 2.
Graph the line.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 202.5
Answer:
The linear equation that represents the relationship between peanuts and walnuts is:
x = 3y
Hence,
The representation of the linear equation in the coordinate plane is:

LESSON 2.8 Understand the y-Intercept of a Line

Quick Review
The y-intercept is the y-coordinate of the point where a line crosses the y-axis. The y-intercept of a proportional relationship is 0.

Practice
The equation y = 5 +0.5x represents the cost of getting a car wash and using the vacuum for x minutes.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 203.1

Question 1.
What is the y-intercept?
Answer:
We know that,
The equation of the line in the y-intercept form is:
y = mx + c
Where,
m is the slope
c is the y-intercept
Now,
The given equation is:
y = 5 + 0.5x
Hence, from the above,
We can conclude that the y-intercept is: 5

Question 2.
What does the y-intercept represent?
Answer:
The y-intercept in the given situation represents that the initial cost of getting a car wash using the Vaccum

LESSON 2.9 Analyze Linear Equations: y = mx + b

Quick Review
An equation in the form y = mx + b, where b=0, has a slope of m and a y-intercept of b. This form is called the slope-intercept form. There is not a proportional relationship between x and y in these cases.

Practice

Question 1.
Graph the line with the equation y = \(\frac{1}{2}\)x – 1.
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 205.1
Answer:
The given equation is:
y = \(\frac{1}{2}\)x – 1
Hence,
The representation of the given equation in the coordinate plane is:

Question 2.
What is the equation of the line?
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 205.2
Answer:
The given graph is:
Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 205.2
From the given graph,
We can observe that
The y-intercept is: 3
Now,
We know that,
The equation of the line in the slope-intercept form is:
y = mx + c
Now,
To find the slope,
The points are: (0, 3), and (3, 0)
So,
Slope (m) = \(\frac{0 – 3}{3 – 0}\)
= \(\frac{-3}{3}\)
= -1
Hence, from the above,
We can conclude that the equation of the line in the slope-intercept form is:
y = -x + 3

Topic 2 Fluency Practice

Pathfinder

Each block below shows an equation and a possible solution. Shade a path from START to FINISH. Follow the equations that are solved correctly. You can only move up, down, right, or left.

Envision Math Common Core 8th Grade Answer Key Topic 2 Analyze And Solve Linear Equations 206.1

enVision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding

Go through the enVision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding regularly and improve your accuracy in solving questions.

enVision Math Common Core 4th Grade Answers Key Topic 1 Generalize Place Value Understanding

Essential Questions:
How are greater numbers written? How can whole numbers be compared? How are place values related?
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 1

enVision STEM Project: Caves
Do Research Use the Internet or other sources to find the depths in feet of the 5 deepest caves in the world.
Journal: Write a Report Include what you found. Also in your report:

  • Make a place-value chart that includes the five depths.
  • Write each depth in expanded form.
  • Use “greater than” or “less than” to compare the depths of two of the caves.

Review What You Know

Vocabulary

Choose the best term from the box. Write it on the blank.

  • expanded form
  • place value
  • number line
  • rounding
  • number name
  • whole numbers

Question 1.
The numbers 0, 1, 2, 3, 4, and so on are called ___________.
Answer:
The numbers 0, 1, 2, 3, 4, and so on are called Whole Numbers.

Question 2.
A number written using only words is written using a __________
Answer:
A number written using only words is written using a Number Name .

Generalize Place Value Understanding 1

Question 3.
Replacing a number with a number that tells about how many or how much is called _________.
Answer:
Replacing a number with a number that tells about how many or how much is called Place Value

Question 4.
_______ is the value given to the place of a digit in a number.
Answer:
Place Value is the value given to the place of a digit in a number.

Comparing Numbers

Compare each set of numbers using >, <, or =.
Question 5.
201 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 21
Answer:
201 < 21
Explanation :
201 is a three digit number
21 is a two digit number
three digit is greater than two digit numbers .

Question 6.
313 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 313
Answer:
313 = 313
Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
313
313
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
313
313
The tens digit is also the same in both numbers.

Step 3
Look at the next digit. Compare the Ones.
313
313
The Ones digit is also the same in both numbers.
so, 313 = 313 .

Generalize Place Value Understanding 2

Question 7.
289 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 290
Answer:

Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
289
290
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
289
290
8 tens < 9 tens
289 < 290 .

Question 8.
7 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 70
Answer:
Explanation :
7 is a one digit number
70 is a two digit number
one digit is lesser than two digit numbers .

Question 9.
725 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 726
Answer:
725 < 726
Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
725
726
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
725
726
The tens digit is also the same in both numbers.

Step 3
Look at the next digit. Compare the Ones.
725
726
5 Ones < 6 Ones
so, 725 < 726 .

Question 10.
82 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 82
Answer:
82 = 82
Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
82
82
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
82
82
The tens digit is also the same in both numbers.

Step 3
Look at the next digit. Compare the Ones.
82
82
The Ones digit is also the same in both numbers.
so,82 = 82

Generalize Place Value Understanding 3

Question 11.
614 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 641
Answer:
614 < 641
Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
614
641
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
614
641
1 Tens < 4 Tens .
614 < 641
614 is lesser than 641 .

Question 12.
618 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 618
Answer:
618 = 618
Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
618
618
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
618
618
The tens digit is also the same in both numbers.

Step 3
Look at the next digit. Compare the Ones.
618
618
The Ones digit is also the same in both numbers.
so, 618 = 618 .

Question 13.
978  Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2  987
Answer:
978  <  987
Explanation :
Step 1
Write the numbers, lining up places. Begin at the left and compare.
978
987
The hundreds digit is the same in both numbers.

Step 2
Look at the next digit. Compare the tens.
978
987
7 Tens < 8 Tens .
978 < 987
978 is lesser than 987 .

Place Value

Tell if the underlined digit is in the ones, tens, hundreds, or thousands place.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 3
Question 14.
9,482
Answer:
9,482 = 9 Thousands place

Question 15.
8,000
Answer:
8,000 = 0 Tens .

Question 16.
1,506
Answer:
1,506 = 0 Hundreds .

Question 17.
8,005
Answer:
8,005 = 8 thousands

Question 18.
5,100
Answer:
5,100 = 1 hundreds .

Question 19.
2,731
Answer:
2,731 = 2 Thousands .

Rounding

Question 20.
Construct Arguments Use the number line to describe how to round 450 to the nearest hundred.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 4
Answer:

500
Explanation :
Nearest 100 of 450 will be 500 .

Pick a Project

PROJECT 1A
How many bones are in your body?
Project: Make a Bones Poster
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 5

PROJECT 1B
Would you like to be a construction manager?
Project: Design a Building
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 6

PROJECT 1С
Which stadium is your favorite?
Project: Create a Stadium Model
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 7

3-ACT MATH PREVIEW

Math Modeling
Page Through
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 8

Lesson 1.1 Numbers Through One Million

Solve & Share
Mrs. Darcy saved ten $100 bills. How much money did Mrs. Darcy save?
I can … read and write numbers through one million in expanded form, with numerals, and using number names.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 9

Look Back! How did you decide how many zeros you needed to write in your answer?
Answer :
Number of bills = 10 .
Bill Amount = $100 .
Total Amount = $100 × 10 = $1000 .
Explanation :
When multiplying whole numbers by 10, simply add a 0 to the end of the number,
so , 100 × 10 = 1000 .

Generalize Place Value Understanding 4

Essential Question
What Are Some Ways to Write Numbers to One Million?
Answer :
10000 × 100 = 1,000,000 .
1000 × 1000 = 1,000,000 .
100000 × 10 = 1,000,000 .

Visual Learning Bridge
The graph shows the attendance at a ballpark over one year. Write the total attendance in expanded form and using number names.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 10

The place-value chart shows periods of three places, starting at the ones period from the right and including the thousands and millions period. Each period is separated by a comma and has three place values: ones, tens, and hundreds.

Each digit in 356,039 is written in its place on the chart. Expanded form shows the sum of the values of each digit.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 11
Expanded form: 300,000 + 50,000 + 6,000 + 30 + 9
Number name: three hundred fifty-six thousand, thirty-nine is written.

Convince Me! Look for Relationships What pattern exists in the three places in each period?

Another Example!
21, 125 can be expanded and written in different ways.
20,000 + 1,000 + 100 + 20 + 5
21,000 + 100 + 25
20,000 + 1,100 + 20 + 5
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 12

Guided Practice

Do You Understand?
Question 1.
What do you notice about the comma in the number on the previous page?
Answer:
The commas separates the periods when number name is written .

Question 2.
Write an example of a number that would include 2 commas.
Answer:
2,000,000 = Two millions .

Do You Know How?
Question 3.
Write 7,320 in expanded form.
Answer:
Expanded form of  7,320 : 7,000 + 300 + 20 + 0 .

Question 4.
Write 55,426 using number names.
Answer:
Number name of 55,426 = fifty five thousands four hundred and twenty six .

Question 5.
In a recent year, 284,604 fans attended the hockey playoffs in Chicago. What digit is in the thousands place in 284,604?
Answer:
284,604 = 4 thousands .

Independent Practice

For 6-8, write each number in expanded form.
Question 6.
7,622
Answer:
Expanded form of 7,622 : 7,000 + 600 + 20 + 2 .

Question 7.
294,160
Answer:
Expanded form of 294,160 : 200,000 + 90,000 + 4,000 + 100 + 60 + 0 .

Question 8.
43,702
Answer:
Expanded form of 43,702 = 40,000 + 3,000 + 700 + 00 + 2 .

For 9-11, write each number name.
Question 9.
1,688
Answer:
Number name of 1,688 : One Thousand six hundred and Eighty Eight .

Generalize Place Value Understanding 5

Question 10.
331,872
Answer:
Number name of 331,872 : Three hundred and thirty one-thousand and Eight hundred and seventy two .

Question 11.
44,444
Answer:
Number name of 44,444 :  Forty four thousand four Hundred and forty four .

Problem Solving

Question 12.
Letitia wrote one thousand, two hundred four in a place-value chart. What mistake did she make?
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 13
Answer:
one thousand, two hundred four : 1,204 .
Explanation :
The mistake is that the four should be written in the Ones place not in tens place value .

Question 13.
Reasoning in 2016, the world’s oldest tree was 5,066 years old. Write the number that is one hundred more using number names.
Answer:
Age of old tree = 5,066 years
One year more than 5,066 years = 5,066 + 100 = 5,166 years .
5,166 : Five thousand One hundred and sixty six .

Question 14.
Jessica wants to buy a new team jacket that costs $35. If Jessica saves $5 a week for 4 weeks and $4 a week for 3 weeks, will she have enough money to buy the team jacket? Explain.
Answer:
$ 32 < $ 35 .
No, she doesn’t have enough money she haves $3 less than the required amount .
Explanation :
Cost of Jacket = $35  .
Number of weeks = 4 weeks
Money saved for each week = $5
Amount saved for 4 weeks = 4 × $ 5 =  $20 .
Number of weeks = 3 weeks
Money saved for each week = $4
Amount saved for 4 weeks = 3 × $ 4 =  $12 .
Total Amount saved = $20 +$12 = $32 .
No, she doesn’t have enough money she haves $3 less than the required amount .

Question 15.
Vocabulary Drew wrote the following sentence: “A period is a group of any 3 three digits in a number.” Do you agree with Drew? If not, how would you correct him?
Answer:
In place value chart, the digits are grouped in the threes in a big number. The number is read from left to right as ………. billion ………. million ……….. thousands ……….. ones.
The place value chart of the International System is given below:
Envision Math Common Core 4th Grade Answers Key Topic 1 Generalize Place Value Understanding Lesson 1.1 Numbers Through One Million Problem Solving Question 15

Question 16.
Higher Order Thinking Two numbers have the same digit in the millions period, the same digits in the thousands period, and the same digits in the ones period. Do these two numbers have the same value? Explain.
Answer:
No,
Explanation :
5,111,666,222
50,111,666,222
Both have same numbers in million,thousands and ones period but they have different numbers in billions periods .

Assessment Practice

Question 17.
Wallace writes the number 72,204 in a place-value chart. Select the places that will be filled on the chart.
☐ Ones
☐ Tens
☐ Thousands
☐ Ten thousands
☐ Hundred thousands
Answer:
Envision Math Common Core 4th Grade Answers Key Topic 1 Generalize Place Value Understanding Lesson 1.1 Numbers Through One Million Problem Solving Question 17

Question 18.
Select all that are equal to 96,014.
☐ 96,000 + 10 + 4
☐ 90,000 + 60,000 + 10 + 4
☐ 90,000 + 6,000 + 4
☐ 90,000 + 6,000 + 10 + 4
☐ 96,000 + 14
Answer:
Envision Math Common Core 4th Grade Answers Key Topic 1 Generalize Place Value Understanding Lesson 1.1 Numbers Through One Million Problem Solving Question 18

Lesson 1.2 Place Value Relationships

Solve & Share
Place-value blocks are shown below for 1, 10, and 100. What patterns in the shapes and sizes of the blocks do you see?
I can… recognize that a digit in one place has ten times the value of the same digit in the place to its right.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 14

Look Back! Describe two ways 100 and 10 are related.
Answer :
Envision-Math-Common-Core-3rd-Grade-Answers-Key-Topic-11-Use-Operations-with-Whole-Numbers-to-Solve-Problems-Lesson-1.2-Place-Value-Relationships-Solve-&-Share

Essential Question
How Are Place Values Related to Each Other?

Visual Learning Bridge
Kiana had bottle caps. She wants to collect ten times as many bottle caps. How many bottle caps will Kiana have in her collection then?
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 15

A hundreds flat represents 100 bottle caps.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 16

To find ten times as many bottle caps, group 10 hundreds flats together.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 17
One thousand is ten times 100.
100 × 10 = 1,000
One hundred is one-tenth of 1,000.
1,000 ÷ 10 = 100
Kiana will have 1,000 bottle caps in her collection.

Convince Me! Generalize Use place-value blocks to model 1 and 10, 10 and 100, 100 and 1,000. What pattern do you see?

Another Example!
Joe scored 2,000 points on a progressive video game. It took him 5 weeks to get his total point value to 20,000. It took him 3 months to get his total point value to 200,000 points. How many times greater than his first score were his points after 5 weeks? After 3 months?
After 5 weeks, Joe’s points were 10 times greater.
After 3 months, Joe’s points were 100 times greater.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 18
2,000 × 10 = 20,000
20,000 × 10 = 200,000
10 × 10 = 100

Guided Practice

Do You Understand?
Question 1.
Is the value of the 2 in 23,406 ten times as great as the value of the 3? Explain.
Answer:
No,
Explanation :
Value of 2 in 23,406 = 20,000 .
Value of 3 in 23,406 = 3,000 .
value of the 2 in 23,406 ten times as great as the value of the 3 = 3,000 × 10 = 30,000 .
So, not equal .

Do You Know How?
For 2, use the relationship between the values of the digits to solve.
Question 2.
Write a number in which the value of the 3 is ten times greater than the value of the 3 in 135,864.
Answer:
345456 .
Explanation:
The value of 3 in 135864 is 30000.We want to write a number that is ten times 30000.We could write any 345456.
Just increase the place value to hundred thousands .

Independent Practice

For 3-5, use the relationship between the values of the digits to solve.
Question 3.
Baseten School District bought 5,000 pencils. They are distributing the pencils evenly to 10 schools in the district. How many pencils will each school get?
Answer:
Number of Pencils = 5,000
Number of schools  = 10 .
Number of pencils each school get = 5,000 ÷ 10 = 500 pencils .
5,000 is ten times the value of 500 .

Question 4.
Place Elementary School is raising money. They raise $90 a week. How long will it take them to raise $900?
Answer:
Amount rise for 1 week = $90
Risen Amount = $900 .
$900  is ten times greater than $90 .
So, Number weeks required to rise Amount = 10 weeks .

Question 5.
A donation of 50 rulers was given to Value Elementary School. The school had 10 times as many erasers donated. How many erasers were donated?
Answer:
Number of Rulers = 50 .
Number of erasers donated =10 times as many erasers donated = 10 × 50 = 500 erasers .

Problem Solving

Question 6.
What can you say about the 3s in 43,862 and 75,398?
Answer:
Place value of 3 in 43,862 = 3,000
Place value of 3 in 75,398 = 300 .
The place value of 3 in 43,862 is ten times greater than the place value in 75,398 .

Question 7.
Critique Reasoning
Mia says in 5,555, all the digits have the same value. Is Mia correct? Explain.
Answer:
No, she is not correct .
Explanation :
Place value from left to right is explained .
Place value of first 5 = 5,000 .
Place value of second 5 = 500 .
Place value of third 5 = 50 .
Place of fourth 5 = 5 .

Question 8.
Number Sense
In 1934, there was an extreme drought in the Great Plains. In the number 1,934, is the value of the 9 in the hundreds place ten times as great as the value of the 3 in the tens place? Explain.
Answer:
No, the place value in Hundreds place is not ten times the place value in tens place .
Explanation :
Place value of 9 in 1934 = 900
Place value of 3 in 1934 = 30 .
9 in the hundreds place ten times as great as the value of the 3 in the tens place = 30 × 10 = 300 .
where 900 and 300 are not equal .

Question 9.
Critique Reasoning Vin says in 4,346, one 4 is 10 times as great as the other 4. Is Vin correct? Explain.
Answer:
No, he is wrong
40 × 100 = 4,000 .
Explanation :
Place of 4 in 4,346 in thousands place = 4,000 .
Place of 4 in 4,346 in tens place = 40 .
Place of 4 in 4,346 in thousands place is 100 times greater than Place of 4 in 4,346 in tens place
40 × 10 = 400 .
40 × 100 = 4,000 .

Question 10.
Describe 2 ways to find the area of the shaded rectangle.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 19
Answer:
Length of shaded rectangle = 3 squares = 3 square unit .
Breadth of Shaded Rectangle = 4 squares = 4 square unit .
Area of rectangle = Length × Breadth = 3 × 4 = 12 unit squares .

Number of squares shaded = 12 square units .
Area of shaded Rectangle = 12 unit squares .

Question 11.
Higher Order Thinking In 448,244, how is the relationship between the first pair of 4s the same as the relationship between the second pair of 4s?
Answer:
448,244
The place of first pair of 44 in 448,244 = 440,000.
The place of Second pair of 44 in 448,244 = 44.
The relationship between the first pair of 4s the same as the relationship between the second pair of 4s = First pair of 44 is 10,000 times greater than Second pair of 44 .
= 44 × 10,000 = 440,000 .

Assessment Practice

Question 12.
Which group of numbers shows the values of the 4s in 44,492?
A. 40,000; 4,000; 400
B. 40,000; 400; 40
C. 4,000; 400; 4
D. 400; 40; 4
Answer:
Option A .
Explanation :
The values of the 4s in 44,492 = 40,000 ; 4,000 ; 400 .

Question 13.
In which number is the value of the red digit ten times as great as the value of the blue digit?
A. 335,531
B. 335,531
C. 335,531
D. 335,531
Answer:

Lesson 1.3 Compare Whole Numbers

Solve & Share
A robotic submarine can dive to a depth of 26,000 feet. Which oceans can the submarine explore all the way to the bottom? Solve this problem any way you choose.
I can … use place value to compare numbers and record my comparisons using <, =, or >.
Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 20

Look Back! Which of the oceans listed is the shallowest? Explain.
Answer :
Compare Depths :
28,232 ; 35,840 ; 23,376 .
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The ten thousands digit 2 is the same in both numbers 28,232 and 23,376 But the number is 3 in 35,840 .
that means 35,840 is the greatest number other than two numbers .
Step 2 :
Look at the next digit. Compare the thousands
28,232
23,376
8 thousands > 3 thousands .
so, 28,232 > 23,376 .
So, 35,840 > 28,232 > 23,376 .

Essential Question
How Do You Compare Numbers?

Visual Learning Bridge
Earth is not perfectly round. The North Pole is 6,356 kilometers from Earth’s center. The equator is 6,378 kilometers from the center. Which is closer to Earth’s center, the North Pole or the equator?
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 21

Step 1
Write the numbers, lining up places. Begin at the left and compare.
6,356
6,378
The thousands digit is the same in both numbers.

Step 2
Look at the next digit. Compare the hundreds.
6,356
6,378
The hundreds digit is also the same in both numbers.

Step 3
The first place where the digits are different is the tens place. Compare the tens.
6,356 5 tens < 7 tens,
6,378 so 6,356 < 6,378.
The North Pole is closer than the equator to Earth’s center.

Convince Me! Reasoning is a whole number with 4 digits always greater than or less than a whole number with 3 digits? Explain.

Guided Practice

Do You Understand?
Question 1. Which place do you use to compare the numbers 60,618 and 60,647?
Answer:
To compare the numbers 60,618 and 60,647 we see Tens place value as the ten thousand , thousand and hundred place values are the same .
1 tens < 4 tens .
so, 60,618 < 60,647 .

Question 2.
Morocco has a total area of 442,300 square kilometers. Uzbekistan has a total area of 447,400 square kilometers. Use >, <, or = to compare the two areas.
Answer:
Total Area of Morocco = 442,300 square kilometers.
Total Area of Uzbekistan = 447,400 square kilometers.
Step 1 :
As , hundred thousand and ten thousands are same compare from thousands place .
Step 2 :
Compare the thousands place .
442,300
447,400
2 thousands < 7 thousands .
442,300 < 447,400 .

Do You Know How?
For 3-7, complete by writing >, =, or < in each O.
Question 3.
2,643 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 2,643
Answer:
2,643 = 2,643
Explanation :
All the thousands , hundreds , tens and ones values are the same .
so, 2,643 = 2,643

Question 4.
62,519 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 64,582
Answer:
62,519 < 64,582
Explanation :
Step 1 :
Write the numbers, lining up places. Begin at the left and compare.
62,519
64,582
The ten thousands digit is the same in both numbers.
Step 2 :
Compare the next digit , the thousands place .
62,519
64,582
2 thousands < 4 thousands .
62,519 < 64,582 .

Question 5.
218,701 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 118,692
Answer:
218,701 > 118,692
Explanation :
Write the numbers, lining up places. Begin at the left and compare.
218,701
118,692
The Hundred thousands digit
2 hundred thousand > 1 hundred thousand
218,701 > 118,692 .

Question 6.
32,467 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 32,467
Answer:
32,467 = 32,467
Explanation :
Step 1 :
All the ten thousand , thousand , hundred , tens and ones digits are same
so, 32,467 = 32,467

Question 7.
19,219 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 19,209
Answer:
19,219 > 19,209
Explanation :
Step 1 :
All the ten thousand , thousand , hundred digits are same so start comparison from tens place .
Step 2  :
Compare ten place
1 ten > 0 ten
19,219 > 19,209 .

Independent Practice

For 8-12, complete by writing >,=, or < in each Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2.
Question 8.
22,873 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 22,774
Answer:
22,873 > 22,774
Explanation :
Step 1  :
The given numbers contains same ten thousand and thousand places . compare from hundred place .
Step 2  :
Compare the next digit that is hundred places .
22,873
22,774
8 hundreds > 7 hundreds .
22,873 > 22,774

Question 9.
912,706 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 912,706
Answer:
912,706 = 912,706
Explanation :
Given numbers have same hundred thousands , ten thousands , thousands , hundreds , tens and ones place values same .
so, 912,706 = 912,706

Question 10.
22,240 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 2,224
Answer:
22,240 > 2,224
Explanation :
The 5 digit number is always greater than the 4 digit number .
So, 22,240 > 2,224

Question 11.
30,000 + 5,000 + 3 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 300,000 + 5,000
Answer:
30,000 + 5,000 + 3 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 300,000 + 5,000
35,003 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 350,000
35,003 < 350,000
Explanation :
The 6 digit number is always greater than the 5 digit number .
so, 35,003 < 350,000

Question 12.
40,000 + 2,000 + 600 + 6 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 240,000 + 3,000 + 10
Answer:
40,000 + 2,000 + 600 + 6 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 240,000 + 3,000 + 10
42,606 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 243,010
42,606 < 243,010
Explanation :
The 6 digit number is always greater than the 5 digit number .
so, 42,606 < 243,010 .

For 13-17, write which place to use when comparing the numbers.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 22
Question 13.
394,284
328,234
Answer:
394,284 > 328,234
Explanation :
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The hundred thousands digit 3 is the same in both numbers 394,284 and 328,234 .
Step 2 :
Look at the next digit. Compare the ten thousands place value .
394,284
328,234
9 ten thousands > 2 ten thousands .
So, 394,284 > 328,234

Question 14.
6,716
6,714
Answer:
6,716 > 6,714
Explanation :
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The thousands digit 6 is the same in both numbers 6,716 and 6,714
Step 2 :
Look at the next digit. Compare the hundreds place value .
The hundreds digit 7 is the same in both numbers 6,716 and 6,714
Step 3 :
Look at the next digit. Compare the tens place value .
The tens digit 1 is the same in both numbers 6,716 and 6,714
Step 4 :
Look at the next digit. Compare the Ones place value .
6 Ones > 4 Ones .
So, 6,716 > 6,714

Question 15.
32,916
32,819
Answer:
32,916 > 32,819
Explanation :
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The ten thousands digit 3 is the same in both numbers 32,916 and 32,819
Step 2 :
Look at the next digit. Compare the hundreds place value .
The thousands digit 2 is the same in both numbers 32,916 and 32,819
Step 3 :
Look at the next digit. Compare the hundreds place value .
9 hundreds > 8 hundreds .
So, 32,916 > 32,819 .

Question 16.
12,217
11,246
Answer:
12,217 > 11,246
Explanation :
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The ten thousands digit 1 is the same in both numbers 12,217 and 11,246
Step 2 :
Look at the next digit. Compare the thousands place value .
2 thousands > 1 thousands .
So, 12,217 > 11,246 .

Question 17.
812,497
736,881
Answer:
812,497 > 736,881
Explanation :
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The hundred thousands digits
8 hundred thousands > 7 hundred thousands .
So, 812,497 > 736,881 .

Problem Solving

For 18-19, use the table at the right.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 23
Question 18.
Which genres at Danny’s Books did NOT sell better than Science?
Answer:
Humor Books did not sell better than Science
Explanation :
As 41,843 > 14,843 .

Question 19.
Which genres at Danny’s Books sold better than Biography?
Answer:
Science , Fantasy and Fiction books sold better than Biography
Explanation :
As , 48143 > 42,843 >41,843 > 41,834 .

Question 20.
Celia bought 3 bags of 4 hamburger buns and 3 bags of 8 hot dog buns. How many hamburger and hot dog buns did Celia buy?
Answer:
Number of Hamburgers buns = 3 bags of 4 hamburger buns = 3 × 4 = 12 buns .
Number of hot dogs buns = 3 bags of 8 hot dog buns = 3 × 8 = 24 buns .
Total Number of hamburger and hot dog buns Celia brought = 12 + 24 buns = 36 buns .

Question 21.
Make Sense and Persevere Write three numbers for which you would use the hundreds place to compare to 35,712.
Answer:
35,712.
The Three numbers are 35,246 ; 35,812 and 35,075 .

Question 22.
enVision® STEM
The Illinoian Stage began about 300,000 years ago. The Wolstonian Stage began about 352,000 years ago. Compare 300,000 to 352,000.
Answer:
300,000 < 352,000.
Explanation :
Step 1:
Write the numbers, lining up places. Begin at the left and compare.
The hundred thousands digit 3 is the same in both numbers 300,000 and 352,000 .
Step 2 :
Look at the next digit. Compare the ten thousands place value .
The ten thousands digit
0 ten thousands < 5 ten thousands .
So, 300,000 < 352,000.

Question 23.
An orchard in Maine has 5,287 apple trees. An orchard in Vermont has 5,729 trees. Use <, >, or = to write a comparison between the number of trees in each orchard.
Answer:
Number of apple trees in Maine orchard = 5,287 apple trees
Number of trees in Vermont orchard = 5,729 trees
5,287 < 5,729
The Vermont orchard have more trees than Maine orchard .

Question 24.
In 2010, the population of Alaska was 710,231. Write this number in expanded form, and write the number name.
Answer:
The population of Alaska = 710,231
Expanded Form : 700,000 + 10,000 + 200 + 30 + 1
Number Name  : Seven Hundred ten thousands Two hundred and thirty one .

Question 25.
Higher Order Thinking Explain how you know 437,160 is greater than 43,716.
Answer:
437,160 > 43,716
Explanation :
437,160 is a 6 digit Number
43,716 is a 5 digit Number .
6 digit number is greater than 5 digit number .

Assessment Practice

Question 26.
Is each comparison true or false?
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 24
Answer:
Envision-Math-Common-Core-3rd-Grade-Answers-Key-Topic-11-Use-Operations-with-Whole-Numbers-to-Solve-Problems-Lesson-1.3-Compare-Whole-Numbers-Assessment-Practice-Question-26

Question 27.
Is each comparison true or false?
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 25
Answer:
Envision-Math-Common-Core-3rd-Grade-Answers-Key-Topic-11-Use-Operations-with-Whole-Numbers-to-Solve-Problems-Lesson-1.3-Compare-Whole-Numbers-Assessment-Practice-Question-27

Lesson 1.4 Round Whole Numbers

Solve & Share
List 7 numbers that round to 300. Use a variety of numbers. Solve this problem any way you choose.
I can … use place value to round numbers.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 26

Look Back! What is the greatest number between 200 and 300 that is closer to 200 than 300? Explain.
Answer :
Envision-Math-Common-Core-3rd-Grade-Answers-Key-Topic-11-Use-Operations-with-Whole-Numbers-to-Solve-Problems-Lesson-1.4-Round-Whole-Numbers-Solve-&-Share

Essential Question
How Can You Round Numbers?

Visual Learning Bridge
James researched 10 facts about Tallahassee, Florida for an assignment. One of the facts he found was the population in Tallahassee for the year 2017. He chose to round the population on his Florida Facts poster. If James rounded the population in 2017 to the nearest thousand, what was the number James displayed?
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 27

Round 181,376 to the nearest thousand. 181,376 is between 181,000 and 182,000.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 28

Find the number 181,376 is closer to.
Mark the halfway point on the number line.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 29
181,376 is to the left of the halfway point.
The poster displayed the population as 181,000.

Convince Me!

Critique Reasoning
Ellie says, “When I round these three numbers, I get the same number for two of them.” Anthony says, “Hmmm, when I round these numbers, I get the same number for all three.” Who is correct? Explain.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 30
Answer :
Both are correct .
Explanation :
Ellie statement is right when we round off all the 3 Numbers to Nearest hundred then
1483 is round off to 1500
1250 is round off to 1300
1454 is round off to 1500
That means two numbers have same round off for 1483 and 1454 numbers .
Antony statement is right when we round off the 3 numbers to Nearest thousands then
1483 is round off to 1000
1250 is round off to 1000
1454 is round off to 1000
that means three numbers have same round off .

Another Example!
You can use place value to round. Round 181,376 to the nearest hundred.
Envision Math Common Core 4th Grade Answers Topic 1 Generalize Place Value Understanding 31

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Guided Practice

Do You Understand?
Question 1.
Explain how to round a number when 3 is the digit to the right of the rounding place.
Answer:
Rounding 1435 to nearest Hundred .
Envision-Math-Common-Core-3rd-Grade-Answers-Key-Topic-11-Use-Operations-with-Whole-Numbers-to-Solve-Problems-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-1
Explanation :

 

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 2.
What number is halfway between 421,000 and 422,000?
Answer:
A number which is halfway between 421,000 and 422,000 is 421,500 .

Do You Know How?
For 3-8, round each number to the place of the underlined digit.
Question 3.
128,955
Answer:
128,955 – Rounding to nearest thousands .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-3

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 4.
85,639
Answer:
85,639 – Rounding to nearest tens .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-4

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 5.
9,924
Answer:
9,924 – Rounding to nearest thousands .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-5

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 6.
194,524
Answer:
194,524 – Rounding to nearest ten thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-6

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 7.
160,656
Answer:
160,656 – Rounding to nearest hundred thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-7
Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 8.
149,590
Answer:
149,590 – Rounding to nearest hundred thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Guided-Practice-Question-8

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Independent Practice

For 9-24, use a number line or place value to round each number to the place of the underlined digit.
Question 9.
493,295
Answer:
493,295 – Rounding to nearest ten thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-9

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 10.
39,230
Answer:
39,230 – Rounding to nearest ten thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-10
Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 11.
277,292
Answer:
277,292 – Rounding to nearest hundred thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-11

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 12.
54,846
Answer:
54,846 – Rounding to nearest Hundred .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-12
Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 13.
4,028
Answer:
4,028 – Rounding to nearest tens .

Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-13

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 14.
638,365
Answer:

638,365 – Rounding to nearest hundred thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-14

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 15.
453,280
Answer:
453,280 – Rounding to nearest thousands .

Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-15

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 16.
17,909
Answer:
17,909 – Rounding to nearest Hundred .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-16
Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 17.
956,000
Answer:

956,000 – Rounding to nearest hundred thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-17
Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 18.
55,460
Answer:
55,460 – Rounding to nearest thousands .

Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-18

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 19.
321,679
Answer:
321,679 – Rounding to nearest ten thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-19

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 20.
417,547
Answer:
417,547- Rounding to nearest tens .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-20

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 21.
117,821
Answer:
117,821 – Rounding to nearest ten thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-21

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 22.
75,254
Answer:
75,254 – Rounding to nearest ten thousands

Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-22

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 23.
949,999
Answer:
949,999 – Rounding to nearest ten thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-23

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 24.
666,821
Answer:
666,821 – Rounding to nearest thousands .
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers- Independent-Practice-Question-24

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Problem Solving

Question 25.
For each zoo in the table, round the attendance to the nearest hundred thousand.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 32
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Problem-Solving-Question-25

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Question 26.
Number Sense Write four numbers that round to 700,000 when rounded to the nearest hundred thousand.
Answer:
The four numbers that round to 700,000 when rounded to the nearest hundred thousand are 702,000 ; 745,000; 699,860 ; 692,480 and 734,955 .

Question 27.
Reasoning
A forest ranger correctly rounded the number of visitors to a park to be 120,000 visitors. Write a number that could be the actual number of visitors if he rounded to the nearest ten thousand.
Answer:
The Number the X is rounded to nearest ten thousand is 120,000 visitors .
the Rounding number is  123,500 .

Question 28.
Amy counted the number of boys and girls at a party. She recorded the results in the tally chart below.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 33
How many more boys than girls were at the party?
Answer:
Number of Girls = 3
Number of Boys = 7
Number of more Boys than Girls at the party = 7 – 3 = 4 boys .

Question 29.
Higher Order Thinking
Liz attended class every day since she started school as a kindergartner. She said she has been in school for about 1,000 days. What numbers could be the actual number of school days if Liz rounded to the nearest ten?
Answer:
Number of days attended to school = 1,000 days
Rounded to the nearest ten 1,000 = 1000 days  .

Assessment Practice

Question 30.
Complete the table. Round each number to the given place.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 34
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Lesson-1.4-Round-Whole-Numbers-Problem-Solving-Question-30

Explanation :

  • Find the digit in the rounding place.
  • Look at the next digit to the right. 3 becomes a 4. If it is 5 or greater, add 1 to the rounding digit. If it is less than 5, leave the rounding digit alone.
  • Change all digits to the right of the rounding place to 0.

Lesson 1.5 Problem Solving

Construct Arguments

Solve & Share

The land areas of three states are shown in the table. Mickey said Alaska’s land area is about 10 times greater than Georgia’s land area. Explain why Mickey is or is not correct. Construct a math argument to support your answer.
I can … construct arguments using what I know about place-value relationships.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 35

Thinking Habits
Be a good thinker! These questions can help you.

  • How can I use numbers, objects, drawings, or actions to justify my argument?
  • Am I using numbers and symbols correctly?
  • Is my explanation clear and complete?

Question :
Look Back! Construct Arguments Mary said Georgia’s land area is about 10 times greater than Hawaii’s land area. Is Mary correct? Construct a math argument to support your answer.
Answer :
Georgia’s land area = 57,513 square miles .
Hawaii’s land area = 6,423 square miles .
10 times area of Hawaii land is = 6,423 square miles × 10 = 60,423 square miles .
57,513 not equal to 60,423
Georgia’s land area not equal to 10 times area of Hawaii land .
So, the statement made is wrong .

Essential Question
How Can You Construct Arguments?

Visual Learning Bridge
The table shows the retail sales per person in three states. Bella says Arizona had more retail sales per person than Massachusetts.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 36
How can you construct a math argument that supports Bella’s conjecture?
I will use what I know about place value to compare numbers.

How can I construct an argument?
I can

  • give an explanation that is clear and complete.
  • use numbers and symbols correctly in my explanation.
  • use numbers, objects, drawings, or actions to justify my argument.
  • use a counterexample in my argument.

Here’s my thinking.
Bella’s statement makes sense.
Start with the greatest place value. The digits are the same in the ten thousands place and in the thousands place. The digits are different in the hundreds place, so that place is compared.
$13,637
$13,533
600 > 500
S0, $13,637 > $13,533.
Bella is correct. Arizona had more retail sales per person than Massachusetts.

Convince Me!
Construct Arguments Gayle said Arizona had more retail sales than Massachusetts because 7 > 3, so $13,637 > $13,533. Construct an argument to explain whether or not Gayle is correct.
Answer :
The digits are the same in the ten thousands place and in the thousands place. The digits are different in the hundreds place, so that place is compared.
$13,637
$13,533
600 > 500 .
So, 13,637 >13,533
Explanation :
Step 1: Always start from the digits at the highest place value.
Step 2: Compare the digits at this place value in both numbers. The number with the bigger digit is greater. Step 3: If the digits are equal, move one place value to the right ????, and repeat Step 2.

Guided Practice

Construct Arguments Use the table on the previous page. Jorge said Massachusetts has more retail sales per person than lowa.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 37

Question 1.
What numbers would you use to construct an argument supporting Jorge’s conjecture?
Answer:
Sales in Lowa = $13,172
Sales in Massachusetts = $13,533

Question 2.
How could you support Jorge’s conjecture?
Answer:
Start with the greatest place value. The digits are the same in the ten thousands place and in the thousands place. The digits are different in the hundreds place, so that place is compared.
$13,172
$13,533
100 < 500
S0, $13,172 < $13,533.
Jorge is correct. Massachusetts had more retail sales per person than Lowa .

Question 3.
Is Jorge’s conjecture true? Justify your answer.
Answer:
Yes, Jorge’s conjecture is true
Explanation :
Start with the greatest place value. The digits are the same in the ten thousands place and in the thousands place. The digits are different in the hundreds place, so that place is compared.
$13,172
$13,533
100 < 500
S0, $13,172 < $13,533.
Jorge is correct. Massachusetts had more retail sales per person than Lowa .

Independent Practice

Construct Arguments
The population of Gerald’s city is three hundred thousand, twenty-seven. Gerald wrote the number as 327,000. Emily lives in a city that has a population of three hundred sixteen thousand, forty-two. Gerald concluded that his city’s population is greater than the population of Emily’s city.
Question 4.
Does Gerald’s explanation make sense? Identify any flaws in Gerald’s thinking
Answer:
Yes,
Population of Gerald’s city = three hundred thousand, twenty-seven = 300,027 .
but Gerald wrote as = 327,000 .

Question 5.
Construct a math argument that explains why Gerald did not write the population of his city correctly.
Answer:
Population of Gerald’s city = three hundred thousand, twenty-seven = 300,027 .
but Gerald wrote as = 327,000 .
Gerald wrote the population in wrongly as she taught it as three hundred and twenty-seven  thousands  .

Question 6.
Correct Gerald’s argument. Explain how to compare the populations of Gerald’s and Emily’s cities.
Answer:
Gerald’s Argument is Wrong .
Population of Gerald’s city = three hundred thousand, twenty-seven = 300,027 .
Population in Emily City = three hundred sixteen thousand, forty-two = 360,042 .
Population in Emily city is greater than Population of Gerald’s city .
Explanation :
Start with the greatest place value. The digits are the same in the hundred thousands place . The digits are different in the tens thousands place, so that place is compared.
300,027
360,042
0 < 60,000
So, 300,027 < 360,042 .
Population in Emily city is greater than Population of Gerald’s city

Problem Solving

Performance Task
Planets
The planets in our solar system are different sizes, as shown below. Nora conjectured that Jupiter’s equator is about 10 times as long as Earth’s equator.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 38

Question 7.
Make Sense and Persevere What information do you have?
Answer:
Length of Earth Equator = 40,030 km
Length of Jupiter Equator =439,264 km
Length of Venus Equator = 38,025 km
Length of Mars Equator = 21,297 km

Question 8.
Be Precise What are possible estimates for the lengths of the equators of Jupiter and Earth?
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 39
Answer:
Length of Earth Equator = 40,030 km
Length of Jupiter Equator =439,264 km
length of Jupiter Equator is greater than length of Earth Equator .

Question 9.
Reasoning What is the relationship between the estimates you found for the lengths of the two equators?
Answer:
Length of Earth Equator = 40,030 km
Length of Jupiter Equator =439,264 km
length of Jupiter Equator is greater than length of Earth Equator .

Question 10.
Construct Arguments Construct an argument justifying Nora’s conjecture.
Answer:
No , Nora statement is wrong
Explanation :
Length of Earth Equator = 40,030 km
Length of Jupiter Equator = 439,264 km
Nora conjectured that Jupiter’s equator is about 10 times as long as Earth’s equator.
10 times the Length of Earth Equator = 40,030 km × 10 = 400,300 km .
10 times the Length of Earth Equator is not equal to Length of Jupiter Equator
400,300 # 439,264 kms .
So, Nora statement is wrong

Topic 1 Fluency Review Activity

Point & Tally
Find a partner. Get paper and pencil. Each partner chooses a different color: Light blue or dark blue.

Partner 1 and Partner 2 each point to a black number at the same time. Both partners multiply those numbers.

If the answer is on your color, you get a tally mark. Work until one partner has twelve tally marks.
I can … multiply within 100.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 40

Topic 1 Vocabulary Review

Understand Vocabulary
Choose the best term from the box. Write it on the blank.
Word List

  • conjecture
  • expanded form
  • greater than symbol (>)
  • Less than symbol (<)
  • millions
  • period
  • place value
  • rounding

Question 1.
A group of three digits, separated by commas, starting from the right is called a ___________.
Answer:
A group of three digits, separated by commas, starting from the right is called a period

Question 2.
A process that determines which multiple of 10, 100, 1,000 (and so on) a number is closest to is called __________.
Answer:
A process that determines which multiple of 10, 100, 1,000 (and so on) a number is closest to is calle rounding

Question 3.
A statement that is believed to be true but has not yet been proven is called a ___________.
Answer:
A statement that is believed to be true but has not yet been proven is called a conjecture

Question 4.
The value given to a place a digit has in a number is called its ___________.
Answer:
The value given to a place a digit has in a number is called its place value

Question 5.
In a number, a period of three places to the left of the thousands period is called the __________ period.
Answer:
In a number, a period of three places to the left of the thousands period is called the Millions period.

For each of these terms, give an example and a non-example.
Question 6 – 8.
Envision Math Common Core Grade 4 Answer Key Topic 1 Generalize Place Value Understanding 41
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Vocabulary-Review-Question-6-to-8

Use Vocabulary in Writing
Question 9.
Describe the value of the 9 in 926,415. Use at least 2 terms from the Word List in your explanation.
Answer:
926,415 – 900,000 – 9 hundred thousands
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Vocabulary-Review-Question-9

Topic 1 Reteaching

Set A pages 5-8

Use a place-value chart to write 301,400.
Expanded form: 300,000 + 1,000 + 400
Number name: three hundred one thousand, four hundred
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 42

Remember that each period has hundreds, tens, ones, and the period name.

Write each number in expanded form and using number names.
Question 1.
7,549
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Reteaching-Set-A-Question-1
Expanded form: 7,000 + 500 + 40 + 9
Number name:  Seven thousand, five hundred and forty Nine .

Question 2.
92,065
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Reteaching-Set-A-Question-2
Expanded form: 90,000 + 2,000 + 60 + 5
Number name:  Ninety Two thousand and Sixty Five .

Set B pages 9-12

Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 43
1,111 = 1,000 + 100 + 10 + 1
As you move left, each 1 × 10 = 10
numeral is 10 times greater 10 × 10 = 100
than the digit on its right. 100 × 10 = 1,000

Remember to use the relationship between the values of the digits.

For 1-2, solve.
Question 1.
How many times greater is the value of the 7 in 70,048 than the value of 7 in 17,992?
Answer:
the value of the 7 in 70,048 = 70,000
the value of 7 in 17,992 = 7,000 .
The value is 7 in 70,048 is 10 times greater than the value of 7 in 17,992  .
7,000 × 10 = 70,000 .
Explanation :
As you move left, each 1 × 10 = 10
numeral is 10 times greater 10 × 10 = 100
than the digit on its right. 100 × 10 = 1,000

Question 2.
Violet has 30 glass tiles. She would like to mosaic tile a tabletop with 10 times that number of tiles. How many tiles does Violet want to use?
Answer:
Number of Violet glass tile = 30
Number of tiles required =10 times that number of tiles = 30 × 10 =  300 titles .

Set C pages 13-16

Use place value to compare 45,423 and 44,897. Start comparing from the left. Look for the first digit that is different.
45,423
44,897
5 > 4
5,000 > 4,000
So, 45,423 > 44,897.

Remember that you can use place value to compare numbers.

Write < or > in the O.
Question 1.
291,846 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 291,864
Answer:
291,846 <  291,864
Explanation :
Start with the greatest place value. The digits are the same in the hundred thousands ,ten thousands place, thousands place and in the hundred’s place . The digits are different in the Tens place, so that place is compared.
291,846
291,864
40 < 60
So, 291,846 <  291,864 .

Question 2.
66,298 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 66,298
Answer:
66,298 = 66,298
Explanation :
Both the numbers have same digits in ten thousand, thousand , hundred , tens and ones place.
So, both the numbers are equal .

Question 3.
88,645 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 87,645
Answer:
88,645 > 87,645
Explanation :
Start with the greatest place value. The digits are the same in ten thousands place  . The digits are different in the thousands place, so that place is compared.
88,645
87,645
8,000 > 7,000
8 thousands > 7 thousands .
So, 88,645 > 87,645

Set D pages 17-20

Round 764,802 to the nearest hundred thousand.
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 44
764,802 is to the right of the halfway point.
So, 764,802 rounds to 800,000.

Remember to find the halfway point to help you round.

For 1-4, use number lines or place value to round each number to the place of the underlined digit.
Question 1.
166,742
Answer:
Round 166,742 to the nearest thousand.
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Reteaching-Set-D-Question-1
166,742 is to the right of the halfway point.
So, 166,742 rounds to 167,000 .

Question 2.
76,532
Answer:
Round 76,532to the nearest thousand.
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Reteaching-Set-D-Question-2
76,532 is to the right of the halfway point.
So, 76,532 rounds to 77,000 .

Question 3.
5,861
Answer:
Round 5,861 to the nearest thousand.
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Reteaching-Set-D-Question-3
5,861 is to the right of the halfway point.
So, 5,861 rounds to 6000 .

Question 4.
432,041
Answer:
Round 432,041 to the nearest thousand.
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Reteaching-Set-D-Question-4
432,041 is to the Left of the halfway point.
So, 432,041 rounds to 432,000 .

Set E pages 21-24

Think about these questions to help you construct arguments.
Thinking Habits

  • How can I use numbers, objects, drawings, or actions to justify my argument?
  • Am I using numbers and symbols correctly?
  • Is my explanation clear and complete?
    Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 44

Remember that you can use math to show why your argument is correct.

According to the 2000 census, the population of a city was 935,426. According to the 2010 census, the population of the same city was 934,578. Taylor says the 2000 population was greater than the 2010 population.
Question 1.
Construct an argument that supports Taylor’s conjecture.
Answer:
Population of the city in 2000 census = 935,426
Population of the city in 2010 census = 934,578
935,426 > 934,578
Taylor statement made is correct .
Explanation :
The digits are the same in the hundred thousands place and in the ten thousands place. The digits are different in the thousands place, so that place is compared.
935,426
934,578
5000 > 4000 .
So, 935,426 > 934,578
Step 1: Always start from the digits at the highest place value.
Step 2: Compare the digits at this place value in both numbers. The number with the bigger digit is greater. Step 3: If the digits are equal, move one place value to the right ????, and repeat Step 2.

Question 2.
In 1870, the population was seventy-two thousand, five hundred six. Lupita wrote 72,560. Construct a math argument that explains whether Lupita wrote the number correctly.
Answer:
Population in 1870 = seventy-two thousand, five hundred six = 76,506 .
Population in 1870 written by Lupita = 72,560
Lupita wrote the number wrongly as she represented 6 in the tens place like seventy-two thousand, five hundred and sixty .

Topic 1 Assessment Practice

Question 1.
Choose all the numbers that round to 100,000 when rounded to the nearest hundred thousand.
☐ 9,999
☐ 89,006
☐ 109,999
☐ 119,999
☐ 999,999
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Assessment-Practice-Question-1

Question 2.
Which symbol makes the comparison true? Write >,=, or < in the Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2.
111,011 Envision Math Common Core 4th Grade Answer Key Topic 1 Generalize Place Value Understanding 2 110,111
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 46
Answer:
111,011 >110,111
The digits are the same in the hundred thousands place and in the ten thousands place. The digits are different in the thousands place, so that place is compared.
111,011
110,111
1 thousand > 0 thousand
So, 111,011 >110,111
Explanation :
Step 1: Always start from the digits at the highest place value.
Step 2: Compare the digits at this place value in both numbers. The number with the bigger digit is greater. Step 3: If the digits are equal, move one place value to the right ????, and repeat Step 2.

Question 3.
Write three numbers that round to 40,000 when rounded to the nearest ten thousand.
Answer:
Three numbers that round to 40,000 when rounded to the nearest ten thousand are 38,990 ; 42,640 and 39,999 .

Question 4.
John wrote the numbers 678,901 and 67,890. How many times greater is the value of 7 in 678,901 than the value of 7 in 67,890?
A. 10,000
B. 1,000
C. 100
D. 10
Answer:
Option D
Explanation :
The place value of 7 in 678,901  = 70,000 .
The place value of 7 in 67,890  = 7,000 .
7,000 × 10 = 70,000 .
The place value of 7 in 678,901 is 10 times greater than The place value of 7 in 67,890 .

Question 5.
Look at the numbers in the table.
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 47
Which number has one digit that represents ten times the value of the digit to its right? Explain.
Answer:
375,595  has the one digit that represents ten times the value of the digit to its right .
Explanation :
The place value of 375,595 is 5,000
The place value of 375,595 is 500
The place value of 375,595 is 5,000 which is ten times the value of the digit to its right that is The place value of 375,595 is 500 .

Question 6
Write the number for 160,060 in expanded form and using number names.
Answer:
160,060
Expanded form – 100,000 + 60,000 + 60

Question 7.
A. For each number, give the whole number that represents the value of the underlined digit. Write your answers in the boxes.
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 48
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Assessment-Practice-Question-7

Question :
B. Look at your answers in Part A. In which number is the value of the underlined digit 10 times the value of the digit to the right of it?
A. 155,349
B. 651,907
C. 947,502
D. 317,055
Answer:
Option D .

Question 8.
Rhode Island has about three hundred fifty-six thousand acres of forested land. What is this number in standard form rounded to the nearest ten thousand?
A. 350,000
B. 400,000
C. 360,000
D. 356,000
Answer:
Rhode Island Area = three hundred fifty-six thousand = 356,000
356,000 rounded to the nearest ten thousand = 360,000 .

Question 9.
Which one of the following comparisons is correct?
A. 65,215 > 65,512
B. 292,200 < 229,200
C. 890,242 < 890,224
D. 101,111 < 111,111
Answer:
Comparisons which are correct is Option D .

Question 10.
Write <, =, or > to complete a true comparison for each pair of numbers.
72,013 _______ 72,103
87,210 _______ 87,210
126,999 _______ 152,999
400,602 _______ 400,062
147,634 _______ 146,734
Answer:
72,013 < 72,103
87,210 = 87,210
126,999 < 152,999
400,602 > 400,062
147,634 > 146,734

Question 11.
The table shows the areas of four states.
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 49
A. Which of the 4 states has the least area? the greatest area? Write the number name for the area of each of these states.
Answer:
Kansas have Least Area= 82,278 square miles .
Montana have Greatest Area = 147,042 square miles .
82,278 = Eighty two thousand two hundred and seventy eight .
147,042 = one hundred and forty seven thousand and forty two .

B. Draw a place-value chart. Record Kansas’s area. Explain how the value of the 2 in the thousands place compares with the value of the 2 in the hundreds place.
Answer:
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Assessment-Practice-Question-11
The value of 2 in one thousands place = 2,000 .
The value of 2 in hundreds place = 200 .
2,000 = 200 × 10
The value of 2 in one thousands place is ten times greater than The value of 2 in hundreds place .

Topic 1 Performance Task

Video Games
Tanji, Arun, and Juanita are playing a video game with 3 levels. The opportunity to earn points increases as the levels of the game increase. To keep track of their progress, Tanji, Arun, and Juanita record and examine their scores at each level.
Question 1.
Use the Level 1 table to answer the following questions.
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 50
Part A
Question :
Tanji noticed he was the only player with 3s in his Level 1 score. What are the values of the 3s in Tanji’s score?
Answer:
Tanji’s Score = 4,337
the values of the 3s in tanji score = 300 and 30 .

Part B
Question :
Arun noticed the 5s in his score were next to each other. Describe the relationship between the 5s in Arun’s score.
Answer:
Arun’s score = 5,519
the values of the 5 s in Arun’s score =5,000 and 500 .
5,000 is ten times the 500 .
the value of one 5 in his score is ten times greater than the value of the other 5

Part C
Question :
Juanita says the value of one 8 in her score is ten times greater than the value of the other 8. Construct an argument and draw a place-value chart to determine if Juanita is correct.
Answer:
Juanita’s Score = 2,868
Envision-Math-Common-Core-4th-Grade-Answers-Key-Topic-1-Generalize-Place-Value-Understanding-Topic-1-Performance-Task-Question-1-Part-C
the value of one 8 in her score is ten times greater than the value of the other 8 is wrong because
the value of one 8 in her score is hundred times greater than the value of the other 8 .
The value of 8 in 2,868 is 800 .
The value of 8 in 2,868 is 8 .
800 = 8 × 100 .

Question 2.
Use the Level 2 table to answer the following questions.
Envision Math Common Core Grade 4 Answers Topic 1 Generalize Place Value Understanding 51
Part A – Question
Juanita had the greatest score at Level 2, followed by Tanji and Arun. Write each player’s score in expanded form to compare each score by place value.
Answer:
Juanita’s Score = 60,114 = 60,000 + 100 + 10 + 4 .
Arun’s Score = 39,207 = 30,000 + 9,000 + 200 + 7
Tanji’s Score = 56,899 = 50,000 + 6,000 + 800 + 90 + 9

Part B – Question
Write each player’s score using number names.
Answer:
Juanita’s Score = 60,114 = Sixty thousand One hundred and fourteen .
Arun’s Score = 39,207 = Thirty nine thousand two hundred and seven .
Tanji’s Score = 56,899 = Fifty Six thousand eight hundred and ninety nine .

Part C – Question
Use >, =, or < to write comparisons between the Level 2 scores.
Answer:
Juanita’s Score = 60,114
Arun’s Score = 39,207
Tanji’s Score = 56,899
60,114 > 56,899  > 39,207 .

Part D – Question
Arun noticed his Level 2 score has a greater value in the thousands place than Tanji’s and Juanita’s Level 2 scores. Round Arun’s score to the nearest thousand.
Answer:
Arun’s Score = 39,207
Rounded to Nearest thousand is
39,207 = 39,000.

Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities

enVision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities

Go through the enVision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities regularly and improve your accuracy in solving questions.

enVision Math Common Core 7th Grade Answers Key Topic 5 Solve Problems Using Equations and Inequalities

Review What You Know!

Vocabulary

Choose the best term from the box to complete each definition.

Question 1.
A statement that contains the symbols
<, >, ≤, or ≥ is called a(n)
Answer:
Inequality,

Explanation:
An open sentence that contains the symbol
< , ≤ , > , or ≥ is called an inequality.
Inequalities can be solved the same way as equations.

Question 2.
Properties that state that performing the same
operation on both sides of an equation will keep
the equation true are called
Answer:
Properties of equation,

Explanation:
The first four properties of equality–those that
deal with operations–allow us to add, subtract,
multiply and divide variables.
They also formally express the idea that when we
perform the same operations on both sides of an equation,
the two sides are still equivalent.
In other words, that we can perform the same
operation on both sides without changing
the values of the variables these are called as
properties of equation.

Question 3.
Addition and subtraction have a(n) ___
because they can “undo” each other.
Answer:
Inverse relationship,

Explanation:
An inverse operation are two operations that undo each other,
e.g. addition and subtraction or multiplication and division.
Can perform the same inverse operation on each side of
an equivalent equation without changing the equality.

Question 4.
Terms that have the same variable are called ___
Answer:
Liketerms,

Explanation:
Terms that have the same variable are called like terms as
like terms are terms that have the same variables and
powers example ax + bx here there are two terms ax, bx
both have x a same variable x and power also same.

Using Equations and Inequalities 1

Properties of Equality

Use properties to solve each equation for x.

Question 5.
x + 9.8 = 14.2
Answer:
x = 4.4,

Explanation:
Given x + 9.8 = 14.2,
after subtracting 9.8 both sides we get
x + 9.8 – 9.8 = 14.2 – 9.8,
x + 0 = 4.4, therefore x = 4.4.

Question 6.
14x = 91
Answer:
x = 6 remainder 7,

Explanation:
Given 14x = 91,
dividing both sides by 14 we get
14x ÷14 = 91 ÷ 14,
x = 91 ÷14,
6
14)91(
     84
7
therefore x = 6 with remainder 7.

Question 7.
\(\frac{1}{3}\)x = 24
Answer:
x = 72,

Explanation:
Given \(\frac{1}{3}\)x = 24,
multiplying both sides by 3 we get
\(\frac{1}{3}\)x X 3 = 24 X 3,
therefore x= 24 X 3= 72.

Like Terms
Combine like terms in each expression.

Question 8.
\(\frac{1}{4}\)k + \(\frac{1}{4}\)m –
\(\frac{2}{3}\)k + \(\frac{5}{9}\)m
Answer:
\(\frac{1}{4}\)k + \(\frac{1}{4}\)m –
\(\frac{2}{3}\)k + \(\frac{5}{9}\)m =
– \(\frac{5}{12}\)k + \(\frac{29}{36}\)m,

Explanation:
Given \(\frac{1}{4}\)k + \(\frac{1}{4}\)m –
\(\frac{2}{3}\)k + \(\frac{5}{9}\)m,
we combine like terms in expression as
(\(\frac{1}{4}\)k – latex]\frac{2}{3}[/latex]k) +
(\(\frac{1}{4}\)m + \(\frac{5}{9}\)m) =
(\(\frac{1}{4}\) – \(\frac{2}{3}\))k +
(\(\frac{1}{4}\) + \(\frac{5}{9}\))m,
before subtracting or adding we make common
denominators for the both terms so
\(\frac{1 X 3 – 2 X 4}{12}\)k +
\(\frac{1 X 9 + 5 X 4}{36}\)m =
\(\frac{3 – 8}{12}\)k + \(\frac{ 9+ 20}{36}\)m = \(\frac{- 5}{12}\)k + \(\frac{29}{36}\)m =
–\(\frac{5}{12}\)k + \(\frac{29}{36}\)m.

Question 9.
-4b + 2w +(-4b) + 8w
Answer:
-8b + 10w,

Explanation:
Given -4b + 2w +(-4b) + 8w we combine like terms as
– 4b + (-4b) and 2 w + 8w =
– 4b + (-4b) + 2w + 8w =
– 8b + 10w, therefore -4b + 2w +(-4b) + 8w = -8b + 10w.

Question 10.
6 – 5z + 8 – 4z + 1
Answer:
-9z + 15 or 15 – 9z,

Explanation:
Given 6 – 5z + 8 – 4z + 1 we combine like terms as
(6 + 8 + 1) and (-5z – 4z) as
6 + 8 + 1 – 5z – 4z = 15 – 9z,
therefore 6 – 5z + 8 – 4z + 1 = 15 – 9z or -9z + 15.

Inequalities

Question 11.
Write an inequality that represents the situation:
A large box of golf balls has more than 12 balls.
Describe how your inequality represents the situation.
Answer:
12 > x is Inequality,

Explanation:
Given a large box of golf balls has more than 12 balls means
12 > x is inequality, where x = the number of golf balls,
inequality states that the number of golf balls is over 12.

Language Development

Fill in the Venn diagram to compare and contrast equations and inequalities.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 1
In the box below, draw pictures to represent the
terms and phrases in the overlap section of your diagram.
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-1

PICK A PROJECT

PROJECT 5A

How many different ways could you sort a basket of vegetables?
PROJECT: COMPARING WITH A VENN DIAGRAM
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 2
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-2

Explanation:
Ways of sorting a basket of vegetables as per
1. A part of a plant used as a food (spinach),
2. Do not contain seeds (potatoes),
3. Distinct in taste – can be sweet (sweet potato), salty,
sore or bitter (bitter gourd),
4. Mostly green in color (cucumber),
5. Supply fiber, vitamins, minerals and trace elements,
6. Involved in vegetative reproduction.

Using Equations and Inequalities 2

PROJECT 5B
Which character would you be from your favorite play? Why?
PROJECT: WRITE A PLAY
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 3

Answer:
Character I would be from my favorite plays is Cinderella,
Always Be Kind No Matter What –
A little kindness goes a long way, and no doubt
Cinderella is a kind soul. Her kindness can make
her seem like a pushover (especially when her evil
stepmother and stepsisters are overloading her with housework!).

Explanation:
Play:

  1. Cinderella is a princess.
  2. She was born to 2 lovely parents.
  3. Her mother dies early, and her father remarries.
  4. But the stepmother and Cinderella’s two
    stepsisters treated her like a servant.
  5. Cinderella meets the Prince once in the forest.
  6. She goes to the royal ball ceremony with the
    fairy godmother’s help and dances with the prince.
  7. The carriage, driver, horse, dress, etc.,
    were all magical and would have returned
    to normal just after the clock struck midnight.
  8. In a hurry to leave the palace before midnight,
    Cinderella forgets her slippers.
  9. The prince traces her back by those slippers and marries her.
  10. They live happily ever after.
    At the end Cinderella kind heart wins,
    so it’s my favorite play.

PROJECT 5C
If you could live in another country, where would you live, and why?
PROJECT: EXCHANGE SOUVENIRS
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 100
Answer:
I would live in Canada,
Many people have the dream of living in another country for at least some time during their life. And with good reason. Their are so many benefits.

Moving overseas can dramatically changes my life for the better.
In fact, there are a whole host of reasons why I decided to move to another country.
Living overseas can offer new opportunities, new lifestyles,
new careers and a new direction, financially better prospects.

Explanation:
I would prefer living in canada because
It’s an absolutely stunning place,
Great job opportunities,
People are family friendly,
The best of modern metropolitan living,
Familiar culture and language,
Free health care,
The Canadian sense of humor,
Canadian crime rates are incredibly low,
Canada is an ‘education superpower’ country,
World leaders in quantum computing,
medical research and space science,
Canada has a wonderfully varied climate,
Canadians breathe some of the cleanest air on this planet,
Great food, Niagara Falls, Cheap living costs,
A country you can be proud of living.

Using Equations and Inequalities 3

PROJECT 5D
How would you prepare for being on a game show?
PROJECT: SOLVE RANDOMIZED EQUATIONS AND INEQUALITIES
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 101

Preparing for being on a game show
1. Studying the format of the show,
2.Taking it seriously and practice,
3. Don’t be guilt – No matter how much I am
losing by keep myself cool and dignity,
4. Stay positive,
5. Enjoy it.

Lesson 5.1 Write Two-Step Equations

Marley collects golf balls. His neighbor Tucker
collects 3 more than twice as many golf balls as Marley.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 3.1
A. How can you use a table to represent the number of golf balls in Marley’s collection, m, and the number of golf balls in Tucker’s collection?
B. How can you use an algebraic expression to represent
the number of golf balls in Tucker’s collection?
a.Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-3

b. Algebraic expression is t = 2m + 3,

Explanation:
Given Marley collects golf balls. His neighbor Tucker
collects 3 more than twice as many golf balls as Marley so
a. The table to represent the number of golf balls in
Marley’s collection m and the number of golf balls
in Tucker’s collection are if Marley’s has 10 golf balls
then Tucker will have 2 X 10 + 3 = 20 + 3 = 23,
if Marley’s has 12 golf balls then Tucker will have
2 X 12 + 3 = 24 + 3 = 27, if Marley’s has 15 golf balls
then Tucker will have 2 X 15 + 3 = 30 + 3 = 33,
if Marley’s has 18 golf balls
then Tucker will have 2 X 18 + 3 = 36 + 3 = 39 and
if Marley’s has 20 golf balls
then Tucker will have 2 X 20 + 3 = 40 + 3 = 43 golf balls
as shown above in the table.
b. As Marley collects golf balls, His neighbor Tucker
collects 3 more than twice as many golf balls as Marley so
the algebraic expression to represent
the number of golf balls in Tucker’s collection is
t = 2m + 3 here t is to represent Tucker and m
is to represent Marley.

Focus on math practices
Look for Relationships How do the terms of the
expression you wrote in Part B relate to the values in the table?
Answer:
Yes, the terms of the expression I wrote in Part B
relate to the values in the table,

Explanation:
As the values in the table of Marley’s collection of
golf balls and Tucker’s collection of golf balls are related
with the terms of expression as Tucker’s collection
of golf balls are dependent on collection of
Marley’s golf balls as twice plus 3 more so values
of table are m = m and t = 2m + 3,
therefore the terms of expression I wrote in Part B
relate to the values in the table.

Essential Question
How does an equation show the relationship between variables and
other quantities in a situation?
Answer:
Yes, an equation show the relationship between
variables and other quantities in a situation with
equality and inequalities signs,

Explanation:
An equation is distinct because it has an equals sign and
that in itself creates a relationship.
Usually, it’s relating the left side to the right side in
terms of that fact that they’re equal to each other and
unlike inequalities which form more of a relation between two quantities that can be greater than or less than.

Try It!

Cole buys a new laptop for $335. He makes a down
payment of $50 and pays the rest in 6 equal monthly payments, p.
What equation represents the relationship between the cost of the laptop and Cole’s payments?
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 3.5Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-5

Explanation:
Given Cole buys a new laptop for $335. He makes a down
payment of $50 and pays the rest in 6 equal monthly payments, p.
The equation cost = $50 + 6 X p represents
the relationship between the cost of the laptop and
Cole’s payments as shown above.

Convince Me!
Why are both multiplication and addition used in the equation that
represents Cole’s monthly payments?
Answer:
Cole’s makes a down payment of $50 first and pays
the rest in 6 equal monthly payments, p not all at same time,
So, both multiplication and addition are used in the equation,

Explanation:
As given Cole buys a new laptop for $335.
He makes a down payment of $50 first and
pays the rest in 6 equal monthly payments, p.
So first we write multiplication as 6 X p then we add
initial down payment $50 in the equation.

Try It!

Marcia and Tamara are running a race. Marcia has run 4 kilometers.
Tamara has completed of the race and is 2.5 kilometers ahead of Marcia.
Write an equation that represents the relationship between the distances each girl has run.
Let k represent the total length of the race in kilometers.
Answer:
Marica = m = 4km,
k = Tamara = t = 2. 5km + m  = 2.5km + 4km = 6.5km,

Explanation:
Given Marcia and Tamara are running a race. Marcia has run 4 kilometers.
Tamara has completed of the race and is 2.5 kilometers ahead of Marcia.
Let k represent the total length of the race in kilometers, m for Marica and t for Tamara and
Marica m = 4 km and Tamara and total length of the race
is t or k = 2.5km + 4km = 6.5km,
Equation that represents the relationship between
the distances each girl has run is  k = t = 2.5 km + m.

Try It!

At the mall, Claire buys a hat that is 60% off and socks that are reduced to $5.49.
She spends a total of $9.49. Let x represent the cost of the hat. Which of the following
equations correctly represents Claire’s shopping trip?
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 3.6
Answer:
Equation correctly representing Claire’s shopping trip is
0.4x + 5.49 = 9.49,

Explanation:
Given at the mall, Claire buys a hat that is 60% off and socks that are reduced to $5.49.
She spends a total of $9.49.
Let x represent the cost of the hat means and 60% off
so 40%x = 0.4x,
Socks = $5.49 and total = $9.49,
So the following equation
correctly represents
Claire’s shopping trip is 0.4x + 5.49 = 9.49.

Using Equations and Inequalities 4

KEY CONCEPT
You can write an equation with more than
one operation to represent a situation.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 3.7Do You Understand?

Question 1.
Essential Question How does an equation show the
relationship between variables and other quantities in a situation?
Answer:
Yes, an equation show the relationship between
variables and other quantities in a situation with
equality and inequalities signs,

Explanation:
An equation is distinct because it has an equals sign and
that in itself creates a relationship.
Usually, it’s relating the left side to the right side in
terms of that fact that they’re equal to each other and
unlike inequalities which form more of a relation between two quantities that
can be greater than or less than.

Question 2.
Use Structure
Do the equations \(\frac{1}{5}\)x + 2 = 6 and
\(\frac{1}{5}\)(x + 2) represent the same situation? Explain.
Answer:
Equations \(\frac{1}{5}\)x + 2 = 6 and
\(\frac{1}{5}\)(x + 2) do not represent the same situation,

Explanation:
Given equations are
1. \(\frac{1}{5}\)x + 2 = 6 and
2. \(\frac{1}{5}\)(x + 2),
1. If we solve \(\frac{1}{5}\)x + 2 = 6 we get
\(\frac{1}{5}\)x = 6 -2,
\(\frac{1}{5}\)x = 4,
x = 4 X 5 = 20 and
2. If we solve \(\frac{1}{5}\)(x + 2) we get
\(\frac{1}{5}\) X x + \(\frac{1}{5}\) X 2 =
\(\frac{1}{5}\) X x = \(\frac{5}{2}\),
x = \(\frac{5}{2}\) X 5,
therefore x = \(\frac{25}{2}\) as
20 ≠ \(\frac{25}{2}\),
So equations \(\frac{1}{5}\)x + 2 = 6 and
\(\frac{1}{5}\)(x + 2) do not represent the same situation.

Question 3.
How do you decide which operations to use when writing an equation?
Answer:
The order of operations is a rule that tells the
correct sequence of steps for evaluating a math expression.
We can remember the order using PEMDAS:
Parentheses, Exponents, Multiplication and
Division (from left to right), Addition and
Subtraction (from left to right).

Explanation:
The order of operations define the priority in which complex equations are solved.
The top priority is your parenthesis, then exponents,
followed by multiplication and division, and
finally addition and subtraction (PEMDAS).

Do You Know How?

Question 4.
Rita started the day with r apps. Then she deleted 5 apps and still had
twice as many apps as Cora has. Write an equation that represents the
number of apps each girl has.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 3.8
Answer:
Equation : r – 5 = 2c,
Cora = 36 apps,
Rita =77 apps,

Explanation:
Given Rita started the day with r apps.
Then she deleted 5 apps and still had
twice as many apps as Cora has.
Let us take Cora as c = 36 apps and
Rita has twice as Cora after deleting 5 apps
means the equation is 2c = r – 5,
and Rita has r = 2c + 5 = 2 X 36 + 5 = 72 + 5 = 77 apps,
therefore, Equation : r – 5 = 2c,
Cora = 36 apps,
Rita =77 apps respectively.

Question 5.
Write a problem that could be represented by the equation 5n – 6 = 19.
Answer:
Jim’s age is 6 years less than 5 times
his younger brother’s age,

Explanation:
Given to write a problem that could be represented
by the equation 5n – 6 = 19, So, lets take Jim’s age at
present is 19 years which is 6 years less than 5 times
his younger brother’s age.

Question 6.
Kayleigh babysat for 11 hours this week. That was 5 fewer than \(\frac{2}{3}\) as
many hours as she babysat last week, h.
Write an equation to represent the number of hours she babysat each week.
Answer:
Equation to represent the number of hours she
babysat each week is \(\frac{2}{3}\)h – 5 = 11,

Explanation:
Given Kayleigh babysat for 11 hours this week.
That was 5 fewer than \(\frac{2}{3}\)
as many hours as she babysat last week, h.
The equation to represent the number of hours she
babysat each week is \(\frac{2}{3}\)h – 5 = 11.

Practice & Problem Solving

Question 7.
A farmer ships oranges in wooden crates. Suppose each orange weighs the same amount.
The total weight of a crate filled with g oranges is 24.5 pounds. Write an equation that
represents the relationship between the weight of the crate and the number of oranges it contains.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 6.4
Answer:
Equation that represents the relationship between
the weight of the crate and the number of
oranges it contains isEnvision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-6

Explanation:
Given a farmer ships oranges in wooden crates.
Suppose each orange weighs the same amount as 0.38lb.
The total weight of a crate filled with g oranges is 24.5 pounds.
So an equation that represents the relationship between
the weight of the crate and the number of oranges
it contains is 24.5 = 15lb + (0.38lb X g) and 1 pound = 1 lb.

Using Equations and Inequalities 5

Question 8.
Jordan wrote the following description:
Three fewer than one fourth of x is 12.
Write an equation to represent the description.
Answer:
Equation: \(\frac{1}{4}\)x – 3 = 12,

Explanation:
Given Jordan wrote the following description:
Three fewer than one fourth of x is 12.
So the equation to represent the description is
\(\frac{1}{4}\)x – 3 = 12.

Question 9.
At a graduation dinner, an equal number of guests were seated at each of 3 large tables, and
7 late-arriving guests were seated at a smaller table. There were 37 guests in all
. If n represents the number of people seated at each of the large tables,
what equation represents the situation?
Answer:
The number of people seated at each of the large tables,
represented by an equation is \(\frac{1}{3}\)n + 7 = 37,

Explanation:
Given at a graduation dinner, an equal number of
guests were seated at each of 3 large tables and
7 late-arriving guests were seated at a smaller table.
There were 37 guests in all. If n represents the
number of people seated at each of the large tables,
The equation representing the situation is
\(\frac{1}{3}\)n + 7 = 37.

Question 10.
Last night, 4 friends went out to dinner at a restaurant.
They split the bill evenly. Each friend paid $12.75 for
his or her meal and each left the same amount for a tip, t.
The total dinner bill including the tip was $61.
What equation could you use to describe the situation?
Answer:
Equation: 4 X $12.75 + 4t  = $61,

Explanation:
Given last night, 4 friends went out to dinner at a restaurant.
They split the bill evenly. Each friend paid $12.75 for
his or her meal and each left the same amount for a tip, t.
The total dinner bill including the tip was $61.
Therefore, equation to describe the situation is
4 X $12.75 + 4t  = $61.

Question 11.
Mia buys 4\(\frac{1}{5}\) pounds of plums.
The total cost after using a coupon for 55¢ off her entire
purchase was $3.23. If c represents the cost of the plums
in dollars per pound, what equation could represent the situation?
Answer:
Equation:  $3.23 = 4\(\frac{1}{5}\) – .55,

Explanation:
Given Mia buys 4\(\frac{1}{5}\) pounds of plums.
The total cost after using a coupon for 55¢ off her entire
purchase was $3.23. If c represents the cost of the plums
in dollars per pound, the equation representing
the situation is $3.23 = 4\(\frac{1}{5}\) – .55,
as 1 dollar = 100 cents.

For 12 and 13, use the equation shown at the right.

Question 12.
Describe a situation that the equation could represent.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 6.5
Answer:
There are 6 groups of children each group there are 15 students
and out of which 3 students are absent, so number of students
present are g represented by equation  g + 3 ÷ 6 = 15,

Explanation:
Given equation as g + 3 ÷ 6 = 15, let us take the situation as
there are 6 groups of children each group there are 15 students
and out of which 3 students are absent,
so number of students present are g, so that g + 3 = 15 X 6,
therefore g + 3 ÷ 6 = 15.

Given the Question 13.
Reasoning Would the situation you wrote for Problem 12
work if the denominator in the equation were doubled?
Explain why or why not.
Answer:
Yes,

Explanation:
Reasoning is that if the situation I wrote for Problem 12
will work if the denominator in the equation were doubled
because the value of number of students present
will change or increase.

Question 14.
You want to buy a pet iguana. You already have $12 and
plan to save $9 per week.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities 6.6
a. Model with Math If w represents the number of weeks until
you have enough money to buy the iguana, what equation
represents your plan to afford the iguana?
b. Explain how you could set up an equation to
find the amount of money you should save each week to
buy the iguana in 6 weeks.
Answer:
a. Equation : $48 = $12 + $9w,
b. Equation to find the amount(a) of money I should save
each week to buy the iguana in 6 weeks is $48 =  $12 + 6a or $60 by 6,

Explanation:
Given I want to buy a pet iguana. I already have $12 and
plan to save $9 per week and iguana costs $48,
a. If w represents the number of weeks until
I have enough money to buy the iguana, the equation
representing my plan to afford the iguana is $48 = $12 + $9w,
b. If the amount(a) of money I should save each week to
buy the iguana in 6 weeks is $48 =  $12 + 6a or a = $60 by 6.

Question 15.
In a certain country, the life expectancy of a
woman born in 1995 was 80.2 years.
Between 1995 and 2005, the life expectancy
increased 0.4 year every 5 years.
a. If L represents the life expectancy of a woman born in 2005,
what equation could you use to represent the situation?
b. Reasoning Could two differences equations be used to
find the value of L? Explain.
Answer:
a. L = 80.2 + 80.2 X 2(0.4),
b. Yes, Equation 1: L = 80.2 + 80.2 X 2(0.4) and
Equation 2: L – 80.2 = 2 X 0.4 X 80.2,

Explanation:
Given in a certain country, the life expectancy of a
woman born in 1995 was 80.2 years.
Between 1995 and 2005, the life expectancy
increased 0.4 year every 5 years.
a. If L represents the life expectancy of a woman born in 2005,
The equation that could be used to represent the situation is
L = 80.2 + 80.2 X 2(0.4), we multiply 80.2 with 2 of 0.4 as
every 5 years it is increased by 0.4 and it means from
1995 and 2005 it will increases twice of 0.4,
b. Yes two equations can be used to find the value of L as
First we calculate L by Equation 1: L = 80.2 + 80.2 X 2(0.4) and
Second we calculate L by Equation 2: L – 80.2 = 2 X 0.4 X 80.2.

Question 16.
Higher Order Thinking Use the equation 5x – 13 = 12
a. Write a description that represents the equation.
b. Of the numbers 1, 2, 3, 4, and 5, which are solutions to the equation?
Answer:
a. Description:
There are few sets of books as x in the library and
each set contains 5 books in that 13 books children
took to home and rest are 12 books in the libray,
So find out how many number of books x were there  in the library,
b. Solution to the equation is 5,

Explanation:
Given the equation 5x – 13 = 12,
a. Wrote the description that represents the equation as
there are few sets of books as x in the library and
each set contains 5 books in that 13 books children
took to home and rest are 12 books in the libray,
So find out how many number of books x were there  in the library,
b. Of the numbers 1, 2, 3, 4, and 5, the solution to the equation
5x – 13 = 12 is 5x = 12 + 13,
5x = 25, therefore x = 25 by 5 = 5, therefore solution to
the equation 5x – 13 = 12 is 5.

Assessment Practice

Question 17.
A garden contains 135 flowers, each of which is either red or yellow.
There are 3 beds of yellow flowers and 3 beds of red flowers.
There are 30 yellow flowers in each yellow flower bed.
PART A
If r represents the number of red flowers in each red flower bed,
what equation could you use to represent the number of red and yellow flowers?

PART B
Write another real-world situation that your equation from Part A could represent.
Answer:
Part A:
Equation to represent the number of red and
yellow flowers is 135 = 3 X 30 + 3r,

Part B:
Real World situation :
There are 135 number of mangoes with fruit seller out of
which 3 baskets mangoes are green in color and 3 baskets of
mangoes are yellow in color and there are total 30 yellow mangoes
in each yellow basket, write an equation to represent the number of
green and yellow mangoes?,

Explanation:
Given a garden contains 135 flowers, each of which is either red or yellow.
There are 3 beds of yellow flowers and 3 beds of red flowers.
There are 30 yellow flowers in each yellow flower bed.
PART A
If r represents the number of red flowers in each red flower bed,
the equation I could use to represent the number of red and
yellow flowers is 135 = 3 X 30 + 3r and
PART B
Wrote another real-world situation that my equation
from Part A could represent as Real World situation :
There are 135 number of mangoes with fruit seller out of
which 3 baskets mangoes are green in color and 3 baskets of
mangoes are yellow in color and there are total 30 yellow mangoes
in each yellow basket, write an equation to represent the number of
green and yellow mangoes? respectively.

Lesson 5.2 Solve Two-Step Equations

Elizabeth wrote the following clues. What is the relationship between the shapes?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.1
Answer:
1. 4c + t = 2s + t, 2 circles = square
2. 3t + 2c = 2c + s, 3 triangles = square
3. s + 2c = 6t, square = 6 triangles – 2 circles,

Explanation:
Elizabeth wrote the clues as
1. 4 circles + 1 triangle = 2 squares and 1 triangle which means
4 circles = 2 squares, so 1 square is equal to 2 circles.
2. 3 triangles + 2 circles = 2 circles + 1 square,
so 1 square is equal to 3 triangles,
3. 1 square + 2 circles = 6 triangles,
so, 1 square = 6 triangles – 2 circles.

Use Structure
How can you use properties of equality to reason about these equations?
Answer:
1. Addition Property,
2. Addition property,
3. Substitution property,

Explanation:
As we know
1. 4c + t = 2s + t,
Addition Property says for all real numbers x, y, and z ,
if x=y , then x + z = y + z, So 4c + t = 2s + t means 4c = 2s,
2. 3t + 2c = 2c + s means as per Addition Property
3t = s,
3. 1 square + 2 circles = 6 triangles we use
substitution property for circles and triangles as
1 square = 2 circles and 1 square = 3 triangles,
So 1 square + 1 square = 2 X 3 triangles =  2 squares,
2 squares = 2 squares.

Focus on math practices
Look for Relationships Complete the equation with only triangles
using the relationships from the clues shown above.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.2
Answer:
Equation : 4c + 1t = 7t,

Explanation:
As we know 4c = 2s and 1s = 3t means 1s = 2c,
so 3t = 2c therefore 4c = 6t as given 4c +1t = 6t + 1t = 7t
therefore the equation with only triangles
using the relationships from the clues shown above is 4c + 1t = 7t.

Essential Question
How is solving a two-step equation similar to solving a one-step equation?
Answer:
Yes, solving a two-step equation is similar to solving a one-step equation,

Explanation:
Solving a one-step or two-step equation:
In solving an equation is to have only variables on
one side of the equal sign and numbers on the
other side of the equal sign.
The other alike is to have the number in front of the variable
equal to one the variable does not always have to be x.
These equations can use any letter as a variable.

Try It!
Andrew rents bowling shoes for $4. He bowls 2 games.
Andrew spent a total of $22. How much was the cost of each game, b?
Complete the bar diagrams, and then solve the problem.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.3
Answer:

Explanation:
Given Andrew rents bowling shoes for $4. He bowls 2 games.
Andrew spent a total of $22. How much was the cost of each game, b,
Completed the bar diagrams as shown above,
Total spent = shoe rental + 2 X cost of each game,
$22 = $4 + 2 X b,
$22 – $4 = $4 + 2b – $4,
$18 = 2b,
Now each game cost is
$18 by 2 = 2b by 2
b = $9, therefore cost of each game is $9.

Convince Me!
What were the two steps you used to solve this equation?
Answer:
Two step equations can be solved in two steps using two different
properties of equality, I used subtraction property and Division property,

Explanation:
Total spent = shoe rental + 2 X cost of each game is given
$22 = $4 + 2 X b,
First we use the subtraction property of equality to
isolate the term containing the variable,
$22 – $4 = $4 + 2b – $4,
$18 = 2b,
Secondly we use the division property of equality to
isolate the variable or get the variable by itself on
one side of the equation as
$18 by 2 = 2b by 2
b = $9, therefore cost of each game is $9.

Try It!
Kirsty ran 24 laps in a charity run and then walked
0.2 kilometer to the presentation table.
The total distance Kirsty traveled was 29.6 kilometers.
What was the distance of each lap? Explain how you solved the problem.
Answer:
1.225km is equal to each laps,

Explanation:
Given Kristy total distance traveled = 29.6km
and Kristy ran 24 laps and later walk 0.2km.
It simply implies that
Total distance traveled = distance covered running + distance covered walking,
Since we know that Total distance traveled = 29.6km,
distance covered running = 24 laps,
distance covered walking = 0.2km,
Distance covered running in km = total distance traveled – distance covered walking,
Distance covered running in km = 29.6km – 0.2km = 29.4km.
To now find the distance for each lap.
Since we have: Distance covered running in km = 29.4km.
Distance covered running in lap = 24 laps i.e 24 laps = 29.4km,
1 lap = x Use cross-multiple 24 laps X x =
29.4km × 1 lap x = 29.4km / 24 x = 1.225km,
Therefore 1.225km is equal to each laps.

KEY CONCEPT
The properties of equality can be applied the same way when
solving two-step equations as when solving one-step equations.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.4
Answer:
Yes, The properties of equality can be applied the same way when
solving two-step equations as when solving one-step equations.
Two step equations can be solved in two steps using two different
properties of equality, We used subtraction property and division property,

Explanation:
We have 5x + 27 = 122,
First we use the subtraction property of equality to
isolate the term containing the variable,
5x + 27 – 27 = 122 – 27,
5x = 95,
Secondly we use the division property of equality to
isolate the variable or get the variable by itself on
one side of the equation as 5x by 5 = 95 by 5
x = 19, therefore the properties of equality can be applied
the same way when solving two-step equations as
when solving one-step equations.

Do You Understand?

Question 1.
Essential Question How is solving a two step equation similar to
solving a one-step equation?
Answer:
Yes, solving a two-step equation is similar to solving a one-step equation,

Explanation:
Solving a one-step or two-step equation:
In solving an equation is to have only variables on
one side of the equal sign and numbers on the
other side of the equal sign.
The other alike is to have the number in front of the variable
equal to one the variable does not always have to be x.
These equations can use any letter as a variable.

Question 2.
Use Structure Preston uses the bar diagram below to represent 4x – 3 = 13.
How would you use the bar diagram to solve for x?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.5
Answer:
By using bar diagram we solve x = 4,

Explanation:
A helpful way to solve problem is to use a bar diagram.
A bar is used to represent the whole. So we label it
with the amount of the whole. Finally, we indicate the required
number of parts with a question mark and determine the value,
By seeing bar diagram we have the total + 3 is divided into
4 parts of x now we solve x as 4x – 3 = 13 by adding 3 both sides,
4x – 3 + 3 = 13 + 3,
4x = 16, Now dividing both sides by 4 we get
4x ÷ 4 = 16 ÷ 4,
x = 4.

Question 3.
Clara has solved the problem 6p – 12 = 72 and says that p = 14.
How can you check to see if Clara is correct?
Answer:
By solving using two-step equation we get p = 14,
we check Clara is correct,

Explanation:
Given Clara equation as 6p – 12 = 72 we solve
First by the addition property of equality to
isolate the term containing the variable,
6p – 12 + 12 = 72 + 12,
6p = 84,
Secondly use the division property of equality to
isolate the variable or get the variable by itself on
one side of the equation as
6p by 6 = 84 by 6, we get p = 14, so checked Clara is correct.

Do You Know How?

Question 4.
Clyde is baking, and the recipe requires 1\(\frac{1}{3}\) cups of flour.
Clyde has 2 cups of flour, but he is doubling the recipe to make twice as much.
How much more flour does Clyde need?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.6
a. Write an equation to represent the problem.
Let c represent the amount of flour Clyde needs.
b. Solve the equation.
Answer:
a. Equation: c = 2 X 1\(\frac{1}{3}\) – 2,
b. Clyde needs \(\frac{2}{3}\) cup more,

Explanation:
Given Clyde is baking, and the recipe requires 1\(\frac{1}{3}\) cups of flour.
Clyde has 2 cups of flour, but he is doubling the recipe to make twice as much.
If c represent the amount of flour Clyde needs the equation is
c = 2 X 1\(\frac{1}{3}\) – 2,
b. Now solving c = 2 X \(\frac{1 X 3 + 1}{3}\) – 2,
c = 2 X \(\frac{4}{3}\) – 2,
c = \(\frac{2 X 4}{3}\) – 2,
c = \(\frac{8}{3}\) – 2,
c = \(\frac{8 – 6}{3}\),
c = \(\frac{2}{3}\) .

Question 5.
Four times a number, n, added to 3 is 47.
a. Write an equation that you can use to find the number.
b. What is the number represented by n?
Answer:
a. Equation: 4n + 3 = 47,
b. The number represented by n is 11,

Explanation:
Given four times a number n added to 3 is 47 means
a. 4 X n + 3 is equal to 47,
therefore the equation is 4n + 3 = 47,
b. Upon solving 4n + 3 = 47 we get value of n, So
first we subtract 3 both sides as
4n + 3  – 3 = 47 – 3,
4n = 44, now we divide both sides by 4 we get
4n ÷ 4 = 44 ÷ 4, so n = 11, therefore the number
represented by n is 11.

Practice & Problem Solving

Question 6.
Use the bar diagram to help you solve the equation 4x – 12 = 16.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.7
Answer:
By using bar diagram we solve x = 7,

Explanation:
A helpful way to solve problem is to use a bar diagram.
A bar is used to represent the whole. So we label it
with the amount of the whole. Finally, we indicate the required
number of parts with a question mark and determine the value,
By seeing bar diagram we have the total + 12 is divided into
4 parts of x now we solve x as 4x – 12 = 16 by adding 12 both sides,
4x – 12 + 12 = 16 + 12,
4x = 28, Now dividing both sides by 4 we get
4x ÷ 4 = 28 ÷ 4,
x = 7.

Question 7.
Complete the steps to solve the equation.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.8
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-8
Explanation:
Completed the steps to solve the equation as shown above
first we subtract 2 both sides as
1/5t + 2 – 2 = 17 – 2,
1/5t = 15, now we multiply both sides by 5 we get
1/5t = 15 X 5,  we get t = 75.

Question 8.
Use the bar diagram to write an equation. Then solve for x.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.9
Answer:
Equation is 3x – 5 = 7 and x = 4,

Explanation:
Using the bar diagram we have 3 times x and subtracting 5
we are getting total as 7, so the equation will be
3x – 5 = 7, now solving to get x first we add 5 both sides as
3x – 5 + 5 = 7 + 5,
3x = 12, now we divide both sides by 3,
3x ÷ 3 = 12 ÷ 3, we get x = 4.

Question 9.
While shopping for clothes, Tracy spent $38 less than 3 times what Daniel spent.
Write and solve an equation to find how much Daniel spent.
Let x represent how much Daniel spent.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.10
Answer:
Equation for Daniel spent is : 3x – 38 = 10,
Daniel spent is $16,

Explanation:
Given while shopping for clothes, Tracy spent $38
less than 3 times what Daniel spent.
Let x represent how much Daniel spent.
So an equation to find how much Daniel spent is
3x – 38 = 10, now we solve by adding 38 both sides as
3x – 38 + 38 = 10 + 38,
3x = 48, now we divide both sides by 3,
3x ÷ 3 = 48 ÷ 3, we get x = 16,
therefore, Daniel spent is $16.

Question 10.
Solve the equation 0.5p – 3.45 = -1.2.
Answer:
p = 4.5,

Explanation:
Given to solve the equation 0.5p – 3.45 = -1.2, first
we add +3.45 both side as
0.5p – 3.45 + 3.45 = -1.2 + 3.45,
0.5p = 2.25, now we divide both sides by 0.5 as
0.5p  ÷ 0.5 = 2.25 ÷ 0.5, we get p = 4.5.

Question 11.
Solve the equation \(\frac{n}{10}\) + 7 = 10.
Answer:
n = 30,

Explanation:
Given to solve the equation \(\frac{n}{10}\) + 7 = 10,
first we subtract 7 both sides as
\(\frac{n}{10}\) + 7 – 7  = 10 – 7,
\(\frac{n}{10}\) = 3, now we multiply both sides by 10 as
\(\frac{n}{10}\) X 10 = 3 X 10,
we get n = 30.

Question 12.
A group of 4 friends went to the movies. In addition to their tickets,
they bought a large bag of popcorn to share for $6.25. The total was $44.25.
a. Write and solve an equation to find the cost of one movie ticket, m.
b. Draw a model to represent the equation.
Answer:
a. 4m + 6.25 = 44.25,
The cost of one movie ticket m is $9.5,
b.
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-9

Explanation:
Given a group of 4 friends went to the movies.
In addition to their tickets, they bought a large bag
of popcorn to share for $6.25. The total was $44.25.
a. Wrote and solved an equation to find the cost of
one movie ticket, m as 4m + 6.25 = 44.25, first we subtract
6.25 both sides as 4m + 6.25 – 6.25 = 44.25 – 6.25,
4m = 38, now we divide both sides by 4 as
4m ÷ 4 = 38 ÷ 4, we get m = $9.5.
b. Drawn a bar diagram model to represent the equation
as shown above.

Question 13.
Oliver incorrectly solved the equation 2x + 4 = 10.
He says the solution is x = 7.
a. What is the correct solution?
b. What mistake might Oliver have made?
Answer:
a. The correct solution is x = 3,
b. Instead of subtracting 4 both sides Oliver added
4 both sides,

Explanation:
Given Oliver incorrectly solved the equation 2x + 4 = 10 as
he says the solution is x = 7,
a. The correct solution is first subtract 4 both sides as
2x + 4 – 4 = 10 – 4,
2x = 6 now divide both sides by 2 as
2x ÷ 2 = 6 ÷ 2, we get x = 3,
b. Mistake Oliver had made is if he says
solution is x = 7 and after solving we are getting
x as 3 means he added more 4 both sides.

Question 14.
Use the equation 4.9x – 1.9 = 27.5.
a. Make Sense and Persevere What two properties of equality
do you need to use to solve the equation?
b. The solution is x = Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.11.
Answer:
a. We need two properties of equality as
1. Addition property of equality and
2. Division property of equality,
b. The solution is x =  6,

Explanation:
Given the equation 4.9x – 1.9 = 27.5,
two properties of equality we need to use to solve the equation is
first addition property of equality by adding 1.9 both sides as
4.9x – 1.9 + 1.9 = 27.5 + 1.9,
4.9x = 29.4 now we use division property of equality by
dividing 4.9 both sides as
4.9x ÷ 4.9 =29.4 ÷ 4.9, we get x = 6,
b. As solved in bit a. we get the solution for x as 6.

Question 15.
Higher Order Thinking
At a party, the number of people who ate meatballs was
11 fewer than \(\frac{1}{3}\) of the total number of people.
Five people ate meatballs
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.111
a. Write and solve an equation to find the number of people at the party.
Let x represent the number of people at the party.
b. Write a one-step equation that has the same solution.
Answer:
a. Equation: 5 = \(\frac{1}{3}\) x – 11,
The number of people at the party are x = 48,
b. One-step equation that has the same solution is
\(\frac{1}{3}\) x   = 16,

Explanation:
At a party, the number of people who ate meatballs was
11 fewer than \(\frac{1}{3}\) of the total number of people.
Five people ate meatballs, So equation to find the number of
people at the party.
a. Let x represent the number of people at the party. Therefore
Equation is \(\frac{1}{3}\) x – 11 = 5,
b. As we have 5 people ate meatballs and 11 are fewer than \(\frac{1}{3}\)
of the total number of people. Total number of people a are equal to 16,
therefore one-step equation that has the same solution is
\(\frac{1}{3}\) x   = 16.

Assessment Practice

Question 16.
In a week, Tracy earns $12.45 less than twice the amount Kayla earns.
Tracy earns $102.45. How much does Kayla earn?
Answer:
Kayla earns = $57.45,

Explanation:
Given in a week, Tracy earns $12.45 less than twice the amount Kayla earns.
Let Kayla earns x and Tracy earns Earns in week= $102.45,
Tracy = 2x – 12.45,
102.45 = 2x – 12.45,
2x = 102.45 + 12.45,
2x = 114.90,
x= 114.90/2,
x = $57.45, therefore Kayla earns 57.45 dollars.

Question 17.
Solve the equation 2x + 4\(\frac{1}{5}\) = 9.
Explain the steps and properties you used.
Answer:
x = \(\frac{12}{5}\),
Properties used are 1. Subtraction property of equation and
2. Division property of equation,

Explanation:
Given the equation as 2x + 4\(\frac{1}{5}\) = 9,
2x + \(\frac{4 X 5 + 1}{5}\) = 9,
2x + \(\frac{21}{5}\) = 9, Now we use subtraction property of equation
both sides we subtract \(\frac{21}{5}\) as
2x + \(\frac{21}{5}\) – \(\frac{21}{5}\) = 9 – \(\frac{21}{5}\),
2x = \(\frac{45 – 21}{5}\),
2x = \(\frac{24}{5}\), Now we use division property of equation so we
divide both sides by 2 as 2x/2 = \(\frac{24}{5}\)/2, we get
x = \(\frac{12}{5}\).

Lesson 5.3 Solve Equations Using the Distributive Property

Explain It!
Six friends go jet skiing. The total cost for the adventure is $683.88,
including a $12 fee per person to rent flotation vests.
Marcella says they can use the equation 6r + 12 = 683.88
to find the jet ski rental cost, r, per person.
Julia says they need to use the equation 6(r + 12) = 683.88.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.12
A. Construct Arguments Whose equation accurately represents the situation?
Construct an argument to support your response.
B. What error in thinking might explain the inaccurate equation?
Answer:
A. Argument : Julia is right the equation 6(r +12) = 683.33 is true,
B. Error in thinking may be instead of 6 persons X $12 fee
per person to rent flotation vests, Marcella says they
can use the equation 6r + 12 = 683.88 not 6r + 6 X 12 = 683.88,

Explanation: Given Six friends go jet skiing. The total cost
for the adventure is $683.88,
including a $12 fee per person to rent flotation vests.
Marcella says they can use the equation 6r + 12 = 683.88
to find the jet ski rental cost, r, per person.
Julia says they need to use the equation 6(r + 12) = 683.88.
A. Argument : Julia is right the equation 6(r +12) = 683.33 is true,
because the total cost for the adventure is $683.88,
including a $12 fee per person to rent flotation vests
means 6 multiply by r in addition to 6 multiply by $12 is
equal to total cost, but not Marcella as she says they
can use the equation 6r + 12 = 683.88,
B. Error in thinking may be instead of 6 persons X $12 fee per
person to rent flotation vests,  Marcella says they can use
the equation 6r + 12 = 683.88 means she is not considering 6
persons rent flotation vests only for one person she is considering,
i.e Marcella is saying in the equation for 1 person rent flotation vests
instead of for six persons which makes inaccurate equation.

Focus on math practices
Use Structure How can you use the correct equation to
determine the jet ski rental cost per person?
Answer:
The correct equation is 6(r + $12) = $683.88 and
the jet ski rental cost per person is $101.98,

Explanation:
Given six friends go jet skiing. The total cost for the adventure is $683.88,
including a $12 fee per person to rent flotation vests.
We have correct equation as 6(r + $12) = $683.88,
r + 12 = 683.88 ÷ 6,
r = (683.88 ÷ 6) – 12,
So the correct equation to determine the jet ski rental cost per person is
r =  $113.98 – $12 = $101.98, therefore The correct equation is 6(r + $12) = $683.88 and
the jet ski rental cost per person is $101.98.

Essential Question
How does the Distributive Property help you solve equations?
Answer:
Distributive property helps in simplifying the problems by
breaking the expressions into addition or subtraction.
The distributive property states that when a factor is multiplied
by the sum or subtract of two numbers, we can multiply each of the two numbers
by that factor and then add or subtract them.

Explanation:
Distributive property is defined as the algebraic property used
to multiply two or more numbers within the parenthesis.
We can say that the distributive property helps in simplifying
the problems by breaking the expressions into addition or subtraction.
It multiplies the number outside parentheses which is equal
to the addition or subtraction of product.
Apart from distributive property, there are two types of properties
known as Commutative and Associative.
This property of multiplication is basically used in addition or subtraction.
To solve equation of distributive property, we need to expand the equation,
find the products and add or subtract.

Try It!

A collector has a box of 32 figurines. The value of each figurine
increased by $2.32 over the past year. The box of figurines is now
worth $114.24. What was the original cost, x, of one figurine?
The original cost of one figurine was Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.13.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.14
Answer:
The original cost of one figurine was $1.25

Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-10
Explanation:
Given a collector has a box of 32 figurines.
The value of each figurine increased by $2.32 over the past year.
The box of figurines is now worth $114.24.
The original cost of one figurine was
32(x + 2.32) = 114.24, Applying distributive property as
32 X x + 32 X 2.32 = 114.24,
32x + 74.24 = 114.24,
32x = 114.24 – 74.24,
32x = 40,
x = 40 ÷ 32,
x= 1.25.

Convince Me!
Can the equation 32x + 2.32 = 114.24 be used to
find the original cost of each figurine in the problem above? Explain.
Answer:
No, the equation 32x + 2.32 = 114.24 cannot be used to
find the original cost of each figurine in the problem above,

Explanation:
As the given equation is 32x + 2.32 = 114.24 cannot be used to
find the original cost of each figurine in the problem above
because here in the equation it is not using the value of
each figurine increased by $2.32 over the past year,
instead of using for 32 figurines it is using only for 1 figurine
it has to use as 32(x + 2.32) = 114.24 not 32x + 2.32 = 114.24,
therefor, the equation 32x + 2.32 = 114.24 cannot be used to
find the original cost of each figurine in the problem above.

Try It!

Use the Distributive Property to solve each equation.
a. –\(\frac{1}{2}\)(b – 6) = 5,
Answer:
b = -2,

Explanation:
Given equation as –\(\frac{1}{2}\)(b – 6) = 5 using
distributive property as –\(\frac{1}{2}\) X b + (-\(\frac{1}{2}\)) X (-6) = 5,
–\(\frac{b}{2}\) + \(\frac{6}{2}\) = 5,
–\(\frac{b}{2}\) + 3 = 5,
–\(\frac{b}{2}\) = 5 – 3,
–\(\frac{b}{2}\) = 2,
-b = 2 X 2,
– b =  4, therefore b = -4.

b. 0.4(x – 0.45) = 9.2,
Answer:
x = 23.45,

Explanation:
Given equation as 0.4(x-0.45) = 9.2 using distributive property as
0.4 X x – 0.4 X 0.45 = 9.2,
0.4x – 0.18 = 9.2,
0.4x = 9.38,
x = 9.38 ÷ 0.4,
x = 23.45.

c. -4(p – 212) = 44,
Answer:
p = 201,

Explanation:
Given equation as -4(p-212) = 44 using distributive property as
-4 X p – 4 X -212 = 44,
-4p + 848 = 44,
-4p = 44 – 848,
p = -804 ÷ -4,
p = 201.

KEY CONCEPT

When solving equations written in the form p(x + 9) = r,
you can use the Distributive Property to multiply the
two terms in the parentheses by the term outside the parentheses.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.15

Do You Understand?

Question 1.
Essential Question How does the Distributive Property help you solve equations?
Answer:
Distributive property helps in simplifying the problems by
breaking the expressions into addition or subtraction.
The distributive property states that when a factor is multiplied
by the sum or subtract of two numbers,
we can multiply each of the two numbers
by that factor and then add or subtract them,
for equation 6(x + 8.5) = 123 we use distributive property
we get x = 12,

Explanation:
Distributive property is defined as the algebraic property used
to multiply two or more numbers within the parenthesis.
We can say that the distributive property helps in simplifying
the problems by breaking the expressions into addition or subtraction.
It multiplies the number outside parentheses which is equal
to the addition or subtraction of product.
Apart from distributive property, there are two types of properties
known as Commutative and Associative.
This property of multiplication is basically used in addition or subtraction.
To solve equation of distributive property, we need to expand the equation,
find the products and add or subtract for equation 6(x + 8.5) = 123
we use distributive property as 6x + 6 X 8.5 = 123,
6x + 51 = 123,
6x = 123 -51,
6x = 72,
x = 72 ÷ 6 = 12.

Question 2.
Make Sense and Persevere How are the terms in parentheses
affected when multiplied by a negative coefficient when the
Distributive Property is applied?
Answer:
If a number outside the parentheses has a negative sign then
the first and simplest way is to change each positive or negative sign
of the terms that were inside the parentheses.
Negative or minus signs become positive or plus signs.
Similarly, positive or plus signs become negative or minus signs,

Explanation:
The terms in parentheses affected when multiplied by a
negative coefficient when the distributive property is applied is the first and
simplest way is to change each positive or negative sign
of the terms that were inside the parentheses.
Negative or minus signs become positive or plus signs.
Similarly, positive or plus signs become negative or minus signs,
Example : If equation is -6(x – 4) if we apply distributive property
-6 X x  -6 X -4,
-6x + 24, means positive x becomes negative 6x and negative 4
has become positive 24 when multiplied by -6.

Question 3.
Reasoning How can an area model help you set up an equation
for a problem situation?
Answer:
Area of a shape is the space occupied by the shape.
The area of the given shape is the shaded part which means
we can set up an equation for a problem situation given,

Explanation:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-11
As shown above the area model for the equation is
(2x + 5)(x+3) as shown.

Do You Know How?

Question 4.
A family of 7 bought tickets to the circus. Each family member also
bought a souvenir that cost $6. The total amount they spent was $147.
How much did one ticket cost?
Answer:
Equation : 7(t + 6) = $147,
The cost of one ticket is $15,

Explanation:
Given a family of 7 bought tickets to the circus. Each family member also
bought a souvenir that cost $6. The total amount they spent was $147.
So the equation is 7(t + 6) = 147 on solving we get cost of one ticket as
7t + 42 = 147,
7t = 147 – 42,
7t = 105,
t = 105/7 = 15,
therefore cost of one ticket is $15.

Question 5.
David reads the problem:
Ally bought a T-shirt and a pair of shorts on sale,
which reduced prices by \(\frac{1}{4}\).
The total savings on the two garments was $10.25.
Find the original price for the pair of shorts.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.16
David says that the original price of the shorts was $41.
Does his answer seem reasonable?
Defend your answer by writing and solving an
equation that represents the situation.
Answer:
No, David answer is not reasonable,
the correct equation is \(\frac{1}{4}\) (18 + s) = 10.25,
where s is price of the shorts,

Explanation:
Given David reads the problem:
Ally bought a T-shirt and a pair of shorts on sale,
which reduced prices by \(\frac{1}{4}\).
The total savings on the two garments was $10.25.
Find the original price for the pair of shorts.
David says that the original price of the shorts was $41.
Now we will check let us take s for price of the shorts, and
price of T-shirt is $18,
So the equation is \(\frac{1}{4}\) (18 + s) = 10.25,
\(\frac{1}{4}\) X 18 + \(\frac{1}{4}\) X s = 10.25,
18 + s = 10.25 X 4,
18 + s = 41,
therefore s = 41 – 18 = 23,
So No, David answer is not reasonable the price of shorts is $23 not $41.

Question 6.
Which of the following shows the correct use of the
Distributive Property when solving (33 – x) = 135.2?
A. (33 – x) = 1_-3 • 135.2
B. \(\frac{1}{3}\) • 33 – \(\frac{1}{3}\)x = \(\frac{1}{3}\) • 135.2
C. \(\frac{1}{3}\) • 33 + \(\frac{1}{3}\)x = 135.2
D. \(\frac{1}{3}\) • 33 – \(\frac{1}{3}\)x = 135.2
Answer:
B. \(\frac{1}{3}\) • 33 – \(\frac{1}{3}\)x = \(\frac{1}{3}\) • 135.2,

Explanation:
Given to show the correct use of the
Distributive Property when solving (33 – x) = 135.2? as
the correct answer is B. \(\frac{1}{3}\) • 33 – \(\frac{1}{3}\)x = \(\frac{1}{3}\) • 135.2, if we multiply both sides with \(\frac{1}{3}\)
we get the correct equation as (33 – x) = 135.2 because
\(\frac{1}{3}\)(33 – x) = \(\frac{1}{3}\) X135.2 means,
\(\frac{1}{3}\) • 33 – \(\frac{1}{3}\)x = \(\frac{1}{3}\) • 135.2,
therefore the correct answer is B. \(\frac{1}{3}\) • 33 – \(\frac{1}{3}\)x = \(\frac{1}{3}\) • 135.2.

Practice & Problem Solving

Leveled Practice For 7-10, use the Distributive Property to solve the equations.

Question 7.
-2(x + 5) = 4
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.17
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-12
Explanation:
Given equation as -2(x + 5) = 4, using Distributive Property
we get -2 X x + (-2 X 5) = 4,
-2x – 10 = 4,
-2x = 14, So x = -14/2 = -7,
therefore x = -7.

Question 8.
3.2 = \(\frac{4}{5}\)(b – 5)
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.18
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-13
Explanation:
Given equation as 3.2 = \(\frac{4}{5}\)(b – 5) using Distributive Property,
we get 3.2 = \(\frac{4}{5}\)  X b + \(\frac{4}{5}\)(-5),
3.2 = \(\frac{4}{5}\)b – 4,
3.2 + 4 = \(\frac{4}{5}\)b,
7.2 = \(\frac{4}{5}\)b,
b = \(\frac{5}{4}\) X 7.2,
b = 5 X 1.8,
therefore b = 9.

Question 9.
\(\frac{1}{8}\)(p + 24) = 9
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.19
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-14
Explanation:
Given equation as \(\frac{1}{8}\)(p + 24) = 9 using Distributive Property,
\(\frac{1}{8}\) X p + \(\frac{1}{8}\) X 24 = 9,
\(\frac{1}{8}\)p + 3 = 9,
\(\frac{1}{8}\) p = 9 – 3,
\(\frac{1}{8}\)p = 6,
p = 6 X 8 = 48 or we can solve \(\frac{1}{8}\)(p + 24) = 9 as
p + 24 = 9 X 8,
p + 24 =72,
p = 72 – 24 = 48.

Question 10.
\(\frac{2}{3}\)(6a + 9) = 20.4
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.20
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-15
Explanation:
Given equation as \(\frac{2}{3}\)(6a + 9) = 20.4 using Distributive Property,
\(\frac{2}{3}\) X 6a + \(\frac{2}{3}\) X 9 = 20.4 9,
4a + 6 = 20.4,
4a = 20.4 – 6,
4a = 14.4,
a = 14.4/4,
a = 3.6.

Question 11.
Use the equation at the right.
a. Make Sense and Persevere If you apply the Distributive Property first to solve the equation,
what operation will you need to use last?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.21
b. If instead you divide first to solve the equation,
what operation would you need to use last?
Answer:
a. We use division operation last, If we apply
the Distributive Property first to solve the equation,
b. We use multiplication last If instead we divide first to solve the equation,

Explanation:
Given equation as 6(\(\frac{d}{3}\) – 5) = 34,
a. If we apply the Distributive Property first to solve the equation,
operation I will need to use last is division as we know
1.. Multiply the term outside of the parentheses by each term
in the parentheses,
2. We combine like terms,
3. we divide to find the final solution,
so 6 X \(\frac{d}{3}\) – 6 X 5 = 34,
2d – 30 = 34,
2d = 34 + 30,
2d = 64,
d = 64/2 = 32,
b. Now If instead I divide first to solve the equation,
operation I would need to use last is
6 X \(\frac{d}{3}\) – 6 X 5 = 34,
\(\frac{d}{3}\) – 5 = 34/6,
\(\frac{d}{3}\) = 5.66 + 5,
\(\frac{d}{3}\) = 10.66
d= 10.66 X 3 = 31.98 ≈ 32, we use multiplication.

Question 12.
A family buys 4 airline tickets online. The family buys travel
insurance that costs $19 per ticket. The total cost is $752.
Let x represent the price of one ticket.
a. Write an equation to represent this situation.
b. What is the price of one ticket?
Answer:
a. Equation: 4(x + 19) = 752,
b. The price of one ticket is $169,

Explanation:
Given a family buys 4 airline tickets online. The family buys travel
insurance that costs $19 per ticket. The total cost is $752.
Let x represent the price of one ticket.
a. As 4 tickets multiplied by each ticket and 4 tickets multiplied
by travel insurance of $19 is equal to $752,
So, the equation is 4(x + 19) = 752,
b. Now solving the equation 4(x + 19) = 752,
4x + 76 = 752,
4x = 752 – 76,
4x = 676,
x = 676/4 = 169, therefore the price of one ticket is $169.

Question 13.
A local charity receives \(\frac{1}{3}\) of funds
raised during a craft fair and a bake sale.
The total amount given to charity was $137.45.
How much did the bake sale raise?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.22
Answer:
The Bake Sale raised funds of $159.75,

Explanation:
Given a local charity receives \(\frac{1}{3}\) of funds
raised during a craft fair and a bake sale.
The total amount given to charity was $137.45 and
Craft Fair raised $252.60, lets take Bake sale raised funds of b,
So \(\frac{1}{3}\)(252.60 + b) = 137.45,
252.60 + b = 137.45 X 3,
252.60 + b = 412.35,
b= 412.35 – 252.60,
b = 159.75,
therefore the Bake Sale raised funds of $159.75.

Question 14.
The solution shown for the equation is incorrect.
a. What is the correct solution?
b. What was the likely error?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.23
Answer:
a. The correct solution is r = 8,
b. Instead of +8 it is showing -8,

Explanation:
a. The given equation is -3(6 – r) = 6,
-3 X 6 -3 X -r = 6,
-18 + 3r = 6,
3r = 6 + 18,
3r = 24,
r = 24/3 = 8,
b. The likely error while solving is -3 X -r it is
+3r, but instead of 3r it is taken as -3r so it is showing
r = -8 but the correct solution is r =8.

Question 15.
Vita wants to center a towel bar on her door that is
27\(\frac{1}{2}\) inches wide.
She determines that the distance from each end of
the towel bar to the end of the door is 9 inches.
Write and solve an equation to find the length of the towel bar.
Answer:
Equation: x + 18 = 27\(\frac{1}{2}\),
The length of the towel bar is 9\(\frac{1}{2}\) inches,

Explanation:
Let x inches be the length of the towel bar,
The width of the door is 9 inches on the each side of the
towel bar so the width of the door is 9 + x + 9 = x + 18 inches.
It is given that the width of the door is 27\(\frac{1}{2}\) inches,
S0 27\(\frac{1}{2}\) inches = x +18,
x = 27\(\frac{1}{2}\) – 18,
x =  \(\frac{55}{2}\) – 18,
x = \(\frac{55 – 36}{2}\),
x = \(\frac{19}{2}\) as numerator is greater than denominator,
we write mixed fraction as x = 9\(\frac{1}{2}\) inches.
therefore, the length of the towel bar is 9\(\frac{1}{2}\) inches.

Question 16.
Higher Order Thinking A cell phone plan is shown at the right.
The rates, which include an unlimited data plan, are the same
each month for 7 months. The total cost for all 7 months is $180.39.
Let m represent the average number of minutes that exceeds
700 minutes each month.
a. Write an equation to represent the given situation.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.24
b. Solve the equation to determine how many additional minutes,
on average, you use each month.
Answer:
a. Equation : 7(19.70 + 1.97 + m X 0.05) = 180.39,
b. 82 additional minutes, on average, can be used each month,

Explanation:
Given a cell phone plan is shown at the right.
The rates, which include an unlimited data plan, are the same
each month for 7 months. The total cost for all 7 months is $180.39.
Let m represent the average number of minutes that exceeds
700 minutes each month.
a. Equation is 7(19.70 + 1.97 + m X 0.05) = 180.39,
b. Solving 7(19.70 + 1.97 + m X 0.05) = 180.39,
21.67 + 0.05m = 180.39/ 7,
0.05m = 25.77 – 21.67,
0.05m = 4.1,
m = 4.1/0.05 = 82,
therefore, 82 additional minutes, on average, can be used each month.

Assessment Practice

Question 17.
Fidel earns a fixed amount, m, for each television he sells, and
an additional $15 if the buyer gets an extended warranty.
Fidel sells 12 televisions with extended warranties, earning $900.
Write an equation to represent the situation.
Then solve the equation to find the amount earned for each television sold.
Answer:
Equation: 12(m +15) = 900,
The amount earned for each television sold is $60,

Explanation:
Given, Amount earned by Fidel for each TV is m,
Additional amount for extended warranty is $15,
Televisions sold are 12,
Amount of televisions sold is $900,
Amount earned by each TV * Number of TV’s +
Additional amount * Number of TV’s = Total amount,
So the equation is 12(m + 15) = 900,
Dividing both sides by 12, we get  m + 15 =  900/12,
m +15 = 75, m =75 – 15 = 60,
therefore, Fidel earns $60 for each television sold.

TOPIC 5 MID-TOPIC CHECKPOINT

Question 1.
Vocabulary Explain how to isolate the variable in the equation
–\(\frac{2}{3}\)n + 7 = 15. Lesson 5-2
Answer:
n = -12,

Explanation:
To isolate a variable is to perform the following steps:
1. Eliminate any fractions present by multiplying both sides
by any denominators present.
2. Get all terms with the variable on the left side of the
equation and all terms without the variable on the other side.
3. Combine the terms on the left side, if possible.
4. Factor out the variable on the left side, if necessary.
5. Divide both sides by the coefficient of the variable,
leaving the variable isolated. Now the equation given is
–\(\frac{2}{3}\)n + 7 = 15, solving
–\(\frac{2}{3}\)n = 15 – 7,
n = – \(\frac{3{2}\) X 8,
n = -12.

Question 2.
Jake paid $13.50 for admission to the county fair and
bought 9 tickets to play games.
If he spent a total of $36, what is the cost, c, of one ticket?
Write and solve an equation. Lessons 5-1 and 5-2
Answer:
Equation: 9c + 13.50 = 36,
The cost of one ticket is $2.5,

Explanation:
Given Jake paid $13.50 for admission to the county fair and
bought 9 tickets to play games.
If he spent a total of $36 and the cost c of one ticket is
Equation 9c + 13.5 = 36,
9c + $13.50 = $36, subtracting 13.5 both sides
9c + 13.50 – 13.5 = 36 -13.5,
9c =  22.5, dividing both sides by 9 we get
9c/9 = 22.5/9,
c = 2.5, therefore cost of one ticket is $2.5.

Question 3.
Select all the equations that are equivalent to \(\frac{1}{2}\)(4 + 8x) = 17.
Lesson 5-3
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.25
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-16
The equations that are equivalent to \(\frac{1}{2}\)(4 + 8x) = 17 are
4x = 15 and 4 + 8x = 34,

Explanation:
Given equation is \(\frac{1}{2}\)(4 + 8x) = 17,
multiplying both side by 2 we get 4 + 8x = 34 and now dividing
both sides by 2 we get 2 + 4x = 17, 4x = 15,
so the equations that are equivalent to \(\frac{1}{2}\)(4 + 8x) = 17 are
4x = 15 and 4 + 8x = 34.

Question 4.
Clara has 9 pounds of apples. She needs 1\(\frac{1}{4}\) pounds
to make one apple pie. If she sets aside 1.5 pounds of
apples to make applesauce, how many pies, p, can she make?
Write and solve an equation. Lessons 5-1 and 5-2
Answer:
Equation: 1\(\frac{1}{4}\)p + 1.5 = 9,
Number of apple pies Clara can make are 6,

Explanation:
Given Clara has 9 pounds of apples.
She needs 1\(\frac{1}{4}\) pounds to make one apple pie.
If she sets aside 1.5 pounds of apples to make applesauce,
Number of pie’s p she can make are
equation is 1\(\frac{1}{4}\)p + 1.5 = 9,
\(\frac{4  X 1 + 1}{4}\)p + 1.5 = 9,
\(\frac{5}{4}\)p + 1.5 = 9,
\(\frac{5}{4}\)p = 9 – 1.5,
\(\frac{5}{4}\)p = 7.5,
5p = 7.5 X 4,
5p = 30,
p = 30/5 = 6, therefore number of apple pies Clara can make are 6.

Question 5.
Solve the equation -4(1.75 + x) = 18. Show your work. Lesson 5-3
Answer:
Solving the equation -4(1.75 + x) = 18 we get x = -6.25,

Explanation:
Given equation is -4(1.75 + x) = 18, dividing both side by -4,
-4(1.75 + x)/-4 = 18/-4,
1.75 + x = – 4.5,
x = – 4.5 -1.75,
x =  – 6.25.

Question 6.
Four friends attend a school play and pay $6.75 per ticket.
Each also buys a Healthy Snack Bag sold by the Theater Club.
If the friends spent a total of $37.00, how much did each Healthy
Snack Bag cost, b? Write and solve an equation. Lessons 5-1, 5-2,5-3
Answer:
Equation:4(6.75 + b) = 37,
Each Healthy Snack Bag cost is $2.5,

Explanation:
Given four friends attend a school play and pay $6.75 per ticket.
Each also buys a Healthy Snack Bag sold by the Theater Club.
If the friends spent a total of $37.00, Now if each Healthy
Snack Bag cost, b then the is equation 4(6.75 + b) = 37,
dividing both sides by 4 we get 6.75 + b = 37/4,
6.75 + b = 9.25,
b = 9.25 – 6.75,
b = 2.5, therefore each Healthy Snack Bag cost is $2.5.

How well did you do on the mid-topic checkpoint? Fill in the stars. Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 11.300

Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-17

TOPIC 5 MID-TOPIC PERFORMANCE TASK

Marven and three friends are renting a car for a trip.
Rental prices are shown in the table.

Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.26

PART A
Marven has a coupon that discounts the rental of a full-size car by $25.
They decide to buy insurance for each day. If the cost is $465,
how many days, d, will they rent the car? Write and solve an equation.
Answer:
Equation : 49d + 21d – 25 = 465,
Number of days they will rent the car is 7 days,

Explanation:
Given Marven has a coupon that discounts the rental of a full-size car by $25.
They decide to buy insurance for each day. If the cost is $465,
So number of many days, d, will they rent the car is
49d + 21d – 25 = 465,
70d = 465 + 25,
70d = 490,
d = 490/70,
d= 7, therefore number of days they will rent the car is 7 days.

PART B
If they still use the coupon, how many days could they rent the small car
with insurance if they have $465 to spend?
Answer:
If they still use the coupon, how many days could they rent the small car
with insurance if they have $465 to spend is 8 days,

Explanation:
If they still use the coupon, Number of days could they rent the small car
with insurance if they have $465 to spend is
39d + 21d – 25 = 465,
60d = 465 + 25,
60d = 490,
d = 8.166, minimum 8 days.

PART C
They rent a car with insurance for 5 days but lost their coupon.
If Marven and the three friends spend $75 each, which car did they rent?
Write and solve an equation to justify your answer.
Answer:
Equation:
5(p + 21) = 4 X 75,
They rent the small car,

Explanation:
If they rent a car with insurance for 5 days but lost their coupon.
If Marven and the three friends spend $75 each means 4 X 75,
Let price be p for the rent of the car,
5(p + 21)  = 4 X 75,
5p + 105 = 300,
5p = 300 – 105,
5p = 195,
p = 195/5,
p = 39, So car did they rent is small car.

Lesson 5.4 Solve Inequalities Using Addition or Subtraction

Explain It!

Selena and Martin are waiting at the bus stop. The number lines show the
possible wait times in minutes, t, for Selena and Martin.

Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.27
A. Construct Arguments Who anticipates a longer wait?
Justify your response with a mathematical explanation.
Answer:
Martin anticipated longer,

Explanation:
Based on inequalities, Martin anticipated a longer waiting time.
This is because he thinks that the bus will arrive greater than 15 minutes.

B. If Selena and Martin both wait 10 minutes for the bus,
whose possible wait time was closer to his or her actual wait time? Explain.
Answer:
Selena is closer,

Explanation:
If both Selena and Martin waited 10 minutes for the bus. Selena is closer to the actual wait time because she anticipated the waiting time for the bus less than 15 minutes before it arrives.

Focus on math practices
Be Precise If Selena and Martin both wait exactly 15 minutes for the bus,
whose possible wait time was closer to his or her actual wait time? Explain.
Answer:
Selena is closer to actual wait time,

Explanation:
If Selena and Martin both wait exactly 15 minutes for the bus.
Selena is closer to the actual wait time.
This is because her possible wait time included 15 minutes.
Her anticipation for the waiting time is exactly the same as the actual waiting time.
Unlike Martin that he anticipated waiting time is greater than 15 mins,
which does not include 15 minutes.

Essential Question
How is solving inequalities with addition and subtraction similar to and
different from solving equations with addition and subtraction?
Answer:
Similarity: Both uses properties of equality or inequality,
Different: An equation has one solution while an inequality has more than one solution,

Explanation:
There is a similarity when solving inequalities with addition and subtraction
from solving equations with addition and subtraction because
both uses properties of equality or inequality.
Inverse relationship between addition and subtraction to
isolate the variable in an equation or inequality. The difference
between the two is the solution for inequality and equation,
There is only one solution for an equation while in an inequality
there can be more than one solution.

Try It!

Kyoko has completed 26 hours of community service.
Her goal is to complete at least 90 hours this semester.
Write and solve an inequality to show how many more hours, h,
Kyoko needs to complete to meet her goal.
Use the number line to graph the solutions.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.28
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-19
Explanation:
Given Kyoko has completed 26 hours of community service.
Her goal is to complete at least 90 hours this semester.
Wrote and solved an inequality to show how many more hours, h,
Kyoko needs to complete to meet her goal as h + 26 ≤ 90,
Used the number line to graph the solutions as shown above.

Convince Me!
Is there more than one solution to the problem about Kyoko?
Explain. Give one value that is a solution and one value that is not a solution.
Answer:
Yes , there more than one solution to the problem about Kyoko,

Explanation:
Yes , there more than one solution to the problem about Kyoko
because of the indicated range for time.
Kyoko must complete at least 64 hours more to achieve her
goal in the community service.
She cannot go beyond 64 hours because it will be more than
the required number of hours. 65 hours is not a solution to the problem.

Try It!

The speed limit on a road drops down to 15 miles per hour around a curve.
Mr. Gerard slows down by 10 miles per hour as he drives around the curve.
He never drives above the speed limit.
At what speed was Mr. Gerard driving before the curve? Graph the solution.
Answer:
Mr. Gerard was driving less than or equal to 25 miles per hour before the curve,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-20
Explanation:
Given the speed limit on a road drops down to
15 miles per hour around a curve.
Mr. Gerard slows down by 10 miles per hour
as he drives around the curve.
He never drives above the speed limit.
The speed Mr. Gerard was driving before the curve is
x – 10 ≤ 15, inequality for the situation,
x – 10 + 10 ≤ 15 + 10, addition property of inequality,
x ≤ 25, his driving speed before the curve,
therefore, Mr. Gerard was driving less than or equal to
25 miles per hour before the curve.

Try It!
Solve the inequality n – 1\(\frac{3}{4}\) ≤ –\(\frac{5}{8}\) Then graph the solution.
Answer:
n ≤ 1\(\frac{1}{8}\)  or n ≤ 1.125,

Explanation:
n – 1\(\frac{3}{4}\) ≤ –\(\frac{5}{8}\),
n – 1\(\frac{3}{4}\) + 1\(\frac{3}{4}\) ≤ –\(\frac{5}{8}\) + 1\(\frac{3}{4}\), addition property of inequality,
n ≤ –\(\frac{5}{8}\) + \(\frac{7}{4}\), simplifying
n ≤ \(\frac{-5 + 14}{8}\),
n ≤ \(\frac{9}{8}\), as numerator is greater we write in mixed fraction as
n ≤ 1\(\frac{1}{8}\)  or n ≤ 1.125.

KEY CONCEPT
Solving inequalities with addition and subtraction is the same as solving equations with addition and subtraction.
Use the inverse relationship between addition and subtraction to isolate the variable.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.29

Do You Understand?

Question 1.
Essential Question How is solving inequalities with addition and subtraction
similar to and different from solving equations with addition and subtraction?
Answer:
Similarity: Both uses properties of equality or inequality,
Different: An equation has one solution while an inequality has more than one solution,

Explanation:
There is a similarity when solving inequalities with addition and subtraction
from solving equations with addition and subtraction because
both uses properties of equality or inequality.
Inverse relationship between addition and subtraction to
isolate the variable in an equation or inequality. The difference
between the two is the solution for inequality and equation,
There is only one solution for an equation while in an inequality
there can be more than one solution.

Question 2.
Be Precise How do the solutions of the two inequalities differ?
Are any of the solutions the same? Explain.
a. x+ 5 < 8 and x + 5 > 8
b. x + 5 ≤ 8 and x + 5 ≥ 8

Answer:
a. The number 3 is not part of the solution for both inequalities,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-21
b. The number 3 is one the solutions for both inequalities,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-22

Explanation:
a. x + 5 – 5 < 8 – 5, (subtraction property of inequality)
x < 3, (solution to the equation) and
x + 5 – 5 > 8 – 5, (subtraction property of inequality)
x > 3, (solution to the equation),
Both solution uses subtraction property of equality,
However the value of the solutions are different,
One is less than 3 while the other is greater than 3.

b. x + 5 – 5 ≤ 8 – 5, (subtraction property of inequality)
x ≤ 3, (solution to the equation) and
x + 5 – 5 ≥ 8 – 5, (subtraction property of inequality)
x ≥ 3, (solution to the equation),
Both solution uses subtraction property of equality,
Both inequalities have 3 as part of the solution.

Question 3.
Reasoning Write two different inequalities in which one of the solutions is
the same as the solution to x – 23 = 191.
Answer:
The inequalities are x- 23 ≤ 191 and x – 23 < 191,
the first inequality has a similar solution to the indicated equation
because of the inequality symbol,

Explanation:
1. x -23 ≤ 191 (first inequality)
x -23 + 23 ≤ 191 + 23 (addition property)
x ≤ 214 (range of solution to the inequality),
x -23 < 191 (second inequality)
x -23 + 23 < 191 + 23 (addition property)
x < 214 (range of solution to the inequality),

2. The solution to the equation is
x – 23 + 23 = 191 + 23,(addition property of equality)
x = 214 (solution to the equation).

Do You Know How?

Question 4.
Solve each inequality. Then graph the solution.
a. x + 5 > 3
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.30
Answer:
x > -2,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-23

Explanation:
x + 5 > 3( inequality),
x + 5 – 5 > 3 – 5, subtract 5 from both sides,
x > -2,
The graph of the solution x > -2 is shown above.

b. x + 5 ≤ 3
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.31
Answer:
x ≤ -2,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-24

Explanation:
x + 5 ≤ 3 (inequality),
x + 5 – 5 ≤ 3 – 5, subtract 5 from both sides,
x ≤ -2,
The graph of the solution x ≤ -2 is shown above.

c. x – \(\frac{3}{2}\) ≤ -3
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.32
Answer:
x ≤ –\(\frac{3}{2}\),
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-25

Explanation:
x – \(\frac{3}{2}\) ≤ -3 (inequality),
x – \(\frac{3}{2}\) + \(\frac{3}{2}\) ≤ -3 + \(\frac{3}{2}\)(adding \(\frac{3}{2}\) both sides),
≤ –\(\frac{3}{2}\),
The graph of the solution x > -2 is shown above.

Question 5.
Elanor is driving below the speed limit on a highway.
a. Write the inequality to show how much faster Elanor can drive without going over the speed limit.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.33
b. Solve the inequality you wrote. By how much can Elanor increase her speed?
Answer:
a. x + 43.5 < 55,
b. Elanor increase her speed by x < 11.5,

Explanation:
a. Let x be the increase in the speed limit,
The inequality for the given situation where Elanor can
drive without going over the speed limit is x + 43.5 < 55,

b. Now we find the value of x in the given inequality is
x + 43.5 < 55, subtracting 43.5 both sides as
x + 43.5 – 43.5 < 55 – 43.5, we get
x< 11.5, So Elanor increase her speed by x < 11.5.

Practice & Problem Solving

Leveled Practice In 6 and 7, fill in the boxes to solve each inequality. Then graph the solutions.

Leveled Practice In 6 and 7, fill in the boxes to solve each inequality. Then graph the solutions.

Question 6.
x + 5 < 7
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.34
Answer:
x < 2,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-26

Explanation:
Given inequality as x + 5 < 7, now we subtract 5 from both sides,
x + 5 – 5 < 7 – 5, we get
x < 2.

Question 7.
x – 4 ≥ 12
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.35
Answer:
x  ≥ 16,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-27

Explanation:
Given inequality as x – 4 ≥ 12, now we add 4 on both sides,
x – 4 + 4 ≥ 12 + 4, we get
x ≥ 16.

Question 8.
Solve x + 10 ≥ 14. Then graph the solution.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.351
Answer:
x ≥ 4,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-28

Explanation:
Given inequality as x + 10 ≥ 14, now we subtract 10 from both sides,
x + 10 – 10 ≥ 14 – 10, we get x ≥ 4.

Question 9.
Solve x – 20 ≤ -11. Then graph the solution.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.36
Answer:
x ≤ 9,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-29

Explanation:
Given inequality as x – 20 ≤ – 11, now we add 20 on both sides,
x – 20 + 20 ≥ -11 + 20, we get
x ≤ 9.

Question 10.
The maximum number of students in a classroom is 26.
If there are 16 students signed up for the art class, how many more
students can join the class without exceeding the maximum?
Answer:
There are at most 10 students who can join the art class,

Explanation:
Let x be the number of students that can join the art class,
x + 16 ≤ 26,
x + 16 – 16 ≤ 26 – 16, subtract 16 from both sides,
x ≤ 10, Therefore there are at most 10 students who can join the art class.

Question 11.
Higher Order Thinking The inequality x + c > -2.55 has the
solution x > 4.85 What is the value of c? How do you know?
Answer:
c = -7.4,

Explanation:
x + c = -2.55,
4.85 + c = -2.55, Substitute the value of x,
4.85 + c – 4.85 = -2.55 – 4.85, subtract -4.85 from both sides,
c = -7.4,
The value of c = -7.4, substitute this to the original inequality,
so that it will make the inequality true,
x + c > -2.55,
x + (-7.4) > -2.55, substitute the value of c,
x + (-7.4) + 7.4 > -2.55 + 7.4, add 7.4 on both sides,
x > 4.85 which is true.

Question 12.
Rina is climbing a mountain. She has not yet reached base camp.
Write an inequality to show the remaining distance, d, in feet
she must climb to reach the peak.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.37
Answer:
Inequality: d + 9,695 > 12,358,
Rina must climb d > 2,663 feet to reach the peak,

Explanation:
The inequality to determine the distance is
d + 9,695 > 12,358,
d + 9,695 – 9,695 > 12,358 – 9,695, subtract 9,695 from both sides,
d > 2,663, therefore, Rina must climb d > 2,663 feet to reach the peak.

Question 13.
On a math test, students must solve the inequality x – 5< 11 and then graph the solution. Mason said the solution is x < 6 and graphed the solution as shown below.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.38
a. What error did Mason make?
b. Show the correct solution on the number line.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.39
Answer:
a. Mason did not use the inverse operations to determine the solution,
b. Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-30

Explanation:
a. Mason did not use the inverse operations to determine the solution of x,
Mason subtracted 5 to the right side when it should have been added this
is the correct way of using inverse operation,
b. x – 5 < 11,
x – 5 + 5 < 11 + 6, adding 5 on both sides,
x < 16, the graph of solution is shown on number line above.

Question 14.
Model with Math Dani’s neighbors paid her to take care of their bird during their vacation.
Dani spent $4 of her earnings on an afternoon snack and $16 on a new book.
Afterward, she had at least $8 left. Write an inequality to represent how much Dani’s neighbors paid her.
Answer:
Inequality : x – (4 + 16) ≥ 8,
Dani’s neighbors paid her x ≥ 28,

Explanation:
Given Dani’s neighbors paid her to take care of their bird
during their vacation.
Dani spent $4 of her earnings on an afternoon snack and
$16 on a new book. Afterward, she had at least $8 left,
Let x be the amount Dani’s neighbors paid her, So the inequality is
x – (4 + 16) ≥ 8, now solving the inequality
x – 20 + 20 ≥ 8 + 20, adding 20 on both sides,
x ≥ 28, therefore, Dani’s neighbors paid her x ≥ 28.

Question 15.
Reasoning The temperature in a greenhouse should be 67°F or higher.
One morning, the heater stopped working.
The temperature dropped 4 degrees before someone fixed the heater.
The temperature was still at least 67°F when the heater started working again.
How can you best describe the temperature in the greenhouse before
the heater stopped working?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.40
Answer:
The temperature in the greenhouse before
the heater stopped working is at least 71°F,

Explanation:
The temperature in a greenhouse should be 67°F or higher.
One morning, the heater stopped working.
The temperature dropped 4 degrees before someone fixed the heater.
The temperature was still at least 67°F when the heater started working again.
Let x be the initial temperature of the heater, so
x – 4 ≥ 67,
x + 4 + 4 ≥ 67 + 4, adding 4 on both sides,
x ≥ 71, therefore, the temperature in the greenhouse before
the heater stopped working is at least 71°F.

Assessment Practice

Question 16.
Ramiro has $21. He wants to buy a skateboard that costs $47.
How much more money does he need to have at least $47?
Write an inequality that represents the situation.
Solve the inequality and graph your solution.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.41
Answer:
Inequality : 47 ≤ x + 21,
26 ≤ x or x ≥ 26,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-31

Explanation:
Given Ramiro has $21. He wants to buy a skateboard that costs $47.
Let x be more money does he need to have at least $47,
So the inequality is 47 ≤ x+21,
47 – 21≤  x + 21 – 21, subtract 21 from both sides,
26 ≤ x, The graph 26 ≤ x or x ≥ 26 is shown above.

Question 17.
Kendra has $7.35 in her purse. She needs at least $2.87 more to buy a special bead.
What is the total amount, x, she needs for the bead?
Which inequalities can be used to represent the situation?
Select all that apply.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.42
Answer:
Inequalities that can be used to represent the
situation x = 10.22 are
1. x – 7.35 ≤ 2.87,
2.  x + 7.35  ≥ 2.87,
3. x – 7.35 ≥ 2.87,
4. x ≥ 10.22,
5. x ≤ 10.22,

Explanation:
Given Kendra has $7.35 in her purse. She needs at least $2.87
more to buy a special bead.
The total amount, x, she needs for the bead is x = 7.35 + 2.87,
So x = 10.22, Given
1. x + 7.35 ≤ 2.87, on solving
x + 7.35 – 7.35 ≤ 2.87 – 7.35, subtracting 7.35 from both sides,
x ≤ 4.48 but we got x = 10.22, So
x + 7.35 ≤ 2.87 is incorrect as x is not equal to x = 10.22 and
also not less than 4.48.

2. x – 7.35 ≤ 2.87, on solving
x – 7.35 + 7.35 ≤ 2.87 + 7.35, adding 7.35 from both sides,
x ≤ 10.22 we got x = 10.22, So
x – 7.35 ≤ 2.87 is correct as x is equal to x = 10.22.

3. x + 7.35 ≥ 2.87,on solving
x + 7.35 – 7.35 ≥ 2.87 – 7.35, subtracting 7.35 from both sides,
x ≥ 4.48 but we got x = 10.22, So
x + 7.35 ≥ 2.87 is correct as x = 10.22 whose value is
greater than 4.48.

4. x – 7.35 ≥ 2.87,on solving
x – 7.35 + 7.35 ≥ 2.87 + 7.35, adding 7.35 from both sides,
x ≥ 10.22 but we got x = 10.22, So
x – 7.35 ≥ 2.87 is correct as x value is equal to 10.22.

5. x ≥ 10.22 is correct as x is equal to x = 10.22.

6. x ≤ 2.87 is incorrect as x is not equal to 10.22 and is not
also less than 2.87.

7. x ≤ 10.22 is correct as x is equal to 10.22.

8. x ≤ 4.48 is incorrect as x value is not equal to 10.22 and
also not less than 4.48.
Therefore,

Inequalities that can be used to represent the
situation x = 10.22 are
1. x – 7.35 ≤ 2.87,
2.  x + 7.35  ≥ 2.87,
3. x – 7.35 ≥ 2.87,
4. x ≥ 10.22,
5. x ≤ 10.22,

Lesson 5.5 Solve Inequalities Using Multiplication or Division

Solve & Discuss It!

Alex and Hope were trying to solve -6x > 24.
Whose inequality shows the solution? Show your work.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 7.43

Answer:
Hope’s work x < -4 shows the inequality to the solution,

Explanation:
Given Alex and Hope were trying to solve -6x > 24.
Hope shows the solution as x < -4 means x values are less than
-4 which will be -5,-6, -7 and so on, if we substitute x as -5,
we get -6(-5) = 30 which is greater than 24,
therefore, Hope’s work x < -4 shows the inequality to the solution,

Construct Arguments Why does more than one value of x
make the inequality true?
Answer:
Yes, because there may be more than one solutions to make
make the inequality true,

Explanation:
Most of the time, an inequality has more than one or even infinity solutions.
For example the inequality: x>3 . The solutions of this inequality are
“all numbers strictly greater than 3”, therefore more than one value of x
make the inequality true.

Focus on math practices
Be Precise What do you notice about the inequality symbols used
in the original inequality and in the correct solution?
Answer:
The inequality symbol in the solution changed,

Explanation:
The inequality symbol (>) changed in the solution,
The inequality symbol became <, This is because of the
negative integer divided to both sides of the inequality.

Essential Question
How is solving inequalities with multiplication and division similar to and
different from solving equations with multiplication and division?
Answer:
Solving inequalities is very similar to solving equations,
but sometimes we have to reverse the symbol.
we must reverse the inequality symbol when we multiply or
divide both sides of the equation by a negative number.
1) It must be multiplication or division (not addition or subtraction)
2) The number being multiplied or divided must be negative.

Explanation:
Solving inequalities is very similar to solving equations,
but sometimes we have to reverse the symbol.

For example:
Multiplication Properties of Inequality,
c is positive,
a<b, then ac<bc ← -2<3,
a>b, then ac>bc ←-2(4)<3(4),
c is negative,
a<b, then ac>bc ← -2<3,
a>b, then ac<bc ←-2(-4)>3(-4),
Division property of inequality,
c is positive,
a<b, then a/c<b/c ← 2<8,
a>b, than a/c>b/c ←2/4<8/4,
c is negative,
a<b, then a/c>b/c ←2<8,
a>b, then a/c<b/c ← 2/-4>8/-4, or

Solving Inequalities is very similar to solving Equations.
The same general technique applies.
That technique for solving equations is:
Whatever we do to one side of the equation,
we have to do to the other side to preserve the equality,
The technique for solving inequalities is:
Whatever we do to one side of the inequality,
we have to do to the other side to preserve the inequality
the techniques are the same.
The technique means:
If we multiply or divide one side of an equation or inequality
by the same number, we have to multiply or divide the other side
of the equation or inequality by the same number.
The difference between solving equations and solving inequalities is:
If you multiply or divide an inequality by a negative number,
then the inequality reverses.
The following examples will show this rule in action.
The first example will be multiplication.
The second example will be division.
The first example starts with:
7 is greater than 5.
Multiply both sides of that inequality by -5 and we get:
7*-5 = -35 on the left side of the inequality.
5*-5 = -25 on the right side of the inequality.
The result is -35 is smaller than -25.
The inequality started as greater than and
became smaller than because we were multiplying both sides
of the inequality by a negative number.
It’s clear to see that 7 really is greater than 5.
It is also clear to see that -35 is less than -25.
The second example is simply the reverse of the first example and starts with:
-35 is smaller than -25.
Divide both sides of this inequality by -5 and we get:
-35 / -5 = 7 on the left side of the inequality.
-25 / -5 = 5 on the right side of the inequality.
The result is 7 is greater than 5.
The inequality started as less than and became greater than
because you were dividing both sides of the inequality by a negative number.
We needed to do that to preserve the inequality.
It’s clear with these numbers that reversing the inequality is
essential when we are multiplying both sides of the inequality or
dividing both sides of the inequality by a negative number.

Try It!

Solve the inequality \(\frac{d}{7}\) > 15. Then graph the solution.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.1
Answer:
d> 105,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-32
Explanation:
Solved the inequality \(\frac{d}{7}\) > 15 as
\(\frac{d}{7}\) > 15, multiplying both sides by 7,
we get d > 105, Shown the graph of the solution d > 105 above.

Convince Me!
Frances solved the inequality 5g ≥ 35. She says that 7 is
a solution to the inequality. Is Frances correct? Explain.
Answer:
Yes, Frances is correct,

Explanation:
Given Frances solved the inequality 5g ≥ 35.
She says that 7 is a solution to the inequality on solving
5g ≥ 35, dividing both sides by 5 we get
g ≥ 7, means g is greater than 7 and we get g is
equal to 7, therefore, Yes, Frances is correct.

Try It!
Solve each inequality. Then graph the solution.

a. 149.76 > -19.2x
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.2
Answer:
-7.8 < x or x > -7.8,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-33
Explanation:
Given to solve inequality 149.76 > -19.2x,
149.76/- 19.2 > -19.2x/-19.2, dividing both sides by -19.2 and
reverse the inequality symbol,
-7.8 < x, shown the value of x as -7.8 < x or x > -7.8 on the graph above.

b. -3.25y < -61.75
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.3
Answer:
-3.25y < -61.75,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-34
Explanation:
Given to solve inequality -3.25y < -61.75,
-3.25y/- 3.25 > -61.75/-3.25, dividing both sides by -3.25 and
reverse the inequality symbol,
y > 19, shown the value of y as y > 19 on the graph above.

Try It!
Solve each inequality. Then graph the solution.

a. \(\frac{k}{-0.5}\) < 12
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.4
Answer:
k> -6,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-33
Explanation:
Given to solve \(\frac{k}{-0.5}\) < 12 inequality,
– 0.5\(\frac{k}{-0.5}\) > – 0.5(12), multiplying both sides by -0.5 and
reverse the inequality symbol,
k > -6, The graph of the solution k > -6 is as shown above.

b. –\(\frac{5}{4}\)h ≥ 25
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.5
Answer:
h ≤ -20,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-34
Explanation:
Given to solve –\(\frac{5}{4}\)h ≥ 25 inequality,
-4 (-\(\frac{5}{4}\)h) ≤ -4(25) multiplying both sides by -4 and
reverse the inequality symbol,
5h ≤ -100,
5h/5 ≤ -100/5, divide both sides by 5,
5h ≤ -20,The graph of the solution 5h ≤ -20 is as shown above.

KEY CONCEPT

Solving inequalities with multiplication and division is the
same as solving equations with multiplication and division
when the values are positive. Use the inverse relationship
between multiplication and division to isolate the variable.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.6
When multiplying or dividing by negative values, the inequality symbol is reversed.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.7

Do You Understand?

Question 1.
Essential Question
How is solving inequalities with multiplication and division
similar to and different from solving equations with multiplication and division?
Answer:
Solving inequalities is very similar to solving equations,
but sometimes you have to reverse the symbol.
we must reverse the inequality symbol when we multiply or
divide both sides of the equation by a negative number.
1) It must be multiplication or division (not addition or subtraction)
2) The number being multiplied or divided must be negative.

Explanation:
Solving inequalities is very similar to solving equations,
but sometimes you have to reverse the symbol.

For example:
Multiplication Properties of Inequality,
c is positive,
a<b, then ac<bc ← -2<3,
a>b, then ac>bc ←-2(4)<3(4),
c is negative,
a<b, then ac>bc ← -2<3,
a>b, then ac<bc ←-2(-4)>3(-4),
Division property of inequality,
c is positive,
a<b, then a/c<b/c ← 2<8,
a>b, than a/c>b/c ←2/4<8/4,
c is negative,
a<b, then a/c>b/c ←2<8,
a>b, then a/c<b/c ← 2/-4>8/-4, or

Solving Inequalities is very similar to solving Equations.
The same general technique applies.
That technique for solving equations is:
Whatever we do to one side of the equation,
we have to do to the other side to preserve the equality,
The technique for solving inequalities is:
Whatever we do to one side of the inequality,
we have to do to the other side to preserve the inequality
the techniques are the same.
The technique means:
If you multiply or divide one side of an equation or inequality
by the same number, we have to multiply or divide the other side
of the equation or inequality by the same number.
The difference between solving equations and solving inequalities is:
If we multiply or divide an inequality by a negative number,
then the inequality reverses.
The following examples will show this rule in action.
The first example will be multiplication.
The second example will be division.
The first example starts with:
7 is greater than 5.
Multiply both sides of that inequality by -5 and we get:
7*-5 = -35 on the left side of the inequality.
5*-5 = -25 on the right side of the inequality.
The result is -35 is smaller than -25.
The inequality started as greater than and
became smaller than because we were multiplying both sides
of the inequality by a negative number.
It’s clear to see that 7 really is greater than 5.
It is also clear to see that -35 is less than -25.
The second example is simply the reverse of the first example and starts with:
-35 is smaller than -25.
Divide both sides of this inequality by -5 and we get:
-35 / -5 = 7 on the left side of the inequality.
-25 / -5 = 5 on the right side of the inequality.
The result is 7 is greater than 5.
The inequality started as less than and became greater than
because you were dividing both sides of the inequality by a negative number.
We needed to do that to preserve the inequality.
It’s clear with these numbers that reversing the inequality is
essential when we are multiplying both sides of the inequality or
dividing both sides of the inequality by a negative number.
or
The similarity is the method of solving it when the
values are positive. The difference is the method of
solving it when the values are negative.

Explanation:
The similarities of solving equation and solving inequalities
Both are used in determining the values of variable
Both can be solved either by one step or two steps
Both have same process when the values are positive
The difference between solving equation and solving inequalities
The properties used when solving equations and solving inequalities
The method of solving equation and inequalities differ
when the values are negative.

Question 2.
Construct Arguments Why is -x < 3 equivalent to x > -3?
Provide a convincing argument.
Answer:
The two inequalities are equivalent,

Explanation:
The variable cannot be negative, therefore it is need
to show the variable as positive.
-x < 3,
-1x/-1 > 3/-1, divide both sides by -1 and
reverse the inequality symbol,
x > -3,
The two inequalities are equivalent, this is because
the first inequality has negative variable.
it needs to be changed into a positive variable.
After solving the first inequality, the result is the same
with the second inequality.

Question 3.
If a, b, and care rational numbers and a > b,
is ac > bc always true? Justify your answer.
Answer:
The given inequality is not always true,

Explanation:
The inequality ac > bc is not always true,
This is because when c is a negative integer,
the inequality becomes false.
Example for this is a = 3, b = 2, c = -1,
Substituting to the inequality ac > bc =
3(-1) > 2(-1) = -3 < -2.

Do You Know How?

Question 4.
Solve each inequality. Then graph the solution.
a. 4x > 12
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.8
Answer:
x > 3,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-35
Explanation:
Given to solve inequality 4x > 12,
4x/4 > 12/4, divide both sides by 4
x > 3, shown the value of x as x > 3 on the graph above.

b. \(\frac{x}{4}\) ≤ -12
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.9
Answer:
x ≤ -48,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-36

Given to solve inequality \(\frac{x}{4}\) ≤ -12
4 X \(\frac{x}{4}\) ≤ 4 X -12, multiplying both sides by 4
x ≤ -48, shown the value of x as x ≤ -48 on the graph above.

c. -4x > 12
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.10
Answer:
x < -3,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-37
Explanation:
Given to solve -4x > 12 inequality,
-4x/-4 < 12/-4 dividing both sides by -4 and
reverse the inequality symbol,
x < -3,
x < -3,The graph of the solution x <-3 is as shown above.

Question 5.
Vanna is saving for a trip. The hotel room will be $298.17 for 3 nights, and
there will be additional fees. What is her daily cost?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.11
a. Write an inequality for the situation.
b. Solve the inequality. Then provide a statement that
represents the solution of the problem.
Answer:
a. 3x ≥ 298.17,
b. x≥ 99.39 , The stay of Vanna in the hotel plus additional cost fees
cost at least $99.39,

Explanation:
Given Vanna is saving for a trip. The hotel room will be $298.17 for 3 nights, and
there will be additional fees, Let x be the daily cost of the stay in the hotel room, So
a. The inequality for the situation is 3x ≥ 298.17,
b. Solving 3x ≥ 298.17 we get daily cost
3x/3 ≥ 298.17/3, dividing both sides by 3 we get
x ≥ 99.39, therefore the stay of Vanna in the hotel plus additional cost fees
cost at least $99.39.

Practice & Problem Solving

Leveled Practice In 6-9, fill in the boxes to solve the inequality.
Then graph the solution.

Question 6.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.12
Answer:
m ≤ 7,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-38

Explanation:
Given to fill the boxes and to solve the 8m ≤ 56 inequality,
8m/8 ≤ 56/8 dividing both sides by 8,
m ≤ 7,The graph of the solution m ≤ 7 is as shown above.

Question 7.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.13
Answer:
x> 6,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-39
Explanation:
Given to fill the boxes and to solve the –\(\frac{4}{3}\)x < -8 inequality,
-3 X \(\frac{4}{3}\) x > -3(-8), multiplying both sides by -3 and
reverse the inequality symbol,
4x > 24,
4x/4 > 24/4, dividing both sides by 4 we get
x > 6, so the graph of the solution x > 6 is as shown above.

Question 8.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.14
Answer:
x < -8,

Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-40
Explanation:
Given to fill the boxes and to solve the -7x > 56 inequality,
– 7x/(-7) < 56/(-8), dividing both sides by -7 and
reverse the inequality symbol,
x < -8, so the graph of the solution x < -8 is as shown above.

Question 9.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.15
Answer:
m ≤ -10,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-41
Explanation:
Given to fill the boxes and to solve the \(\frac{m}{-5}\) ≥ 2 inequality,
-5 X \(\frac{m}{-5}\) ≤ -5(2), multiplying both sides by -5 and
reverse the inequality symbol,
m ≤ -10, so the graph of the solution m ≤ -10 is as shown above.

Question 10.
Kyra and five friends shared a bag of fruit snacks.
Each person got no more than 3 fruit snacks.
The inequality x ÷ 6 ≤ 3 represents this situation.
Solve the inequality to find the possible numbers of fruit
snacks that were in the bag.
Answer:
There are at most 18 fruit snacks that were in the bag,

Explanation:
Given Kyra and five friends shared a bag of fruit snacks.
Each person got no more than 3 fruit snacks.
The inequality x ÷ 6 ≤ 3 represents this situation the
possible numbers of fruit snacks that were in the bag are
x ÷ 6 ≤ 3,
6 X (x ÷ 6) ≤ 6 X 3, multiplying both sides by 6,
x ≤ 18, therefore, there are at most 18 fruit snacks that were in the bag.

Question 11.
Over the next 17 months, Eli needs to read more than 102 e-books.
The inequality 17x > 102 represents the number of e-books he
needs to read per month.
Solve the inequality to find the number of e-books Eli needs to read per month.
Answer:
Eli needs to read at least 6 e -books per month,

Explanation:
Given over the next 17 months, Eli needs to read more than 102 e-books.
The inequality 17x > 102 represents the number of e-books he
needs to read per month. Now solving the inequality to
find the number of e-books Eli needs to read per month as
17x > 102,
17x ÷17 > 102 ÷17, dividing both sides by 17,
x > 6, therefore, Eli needs to read at least 6 e -books per month.

Question 12.
Brittney can spend no more than $15 for new fish in her aquarium.
a. Let f be the number of fish she can buy. What inequality represents the problem?
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.16
b. How many fish can Brittney buy?
Answer:
a. 3f ≤ 15,
b. Brittney can buy no more than 5 fishes,

Explanation:
Given Brittney can spend no more than $15 for new fish in her aquarium.
a. Let f be the number of fish she can buy.
So inequality that represents the problem is 3f ≤ 15,
b. Solving the inequality equation 3f ≤ 15,
3f ÷ 3 ≤ 15 ÷ 3, dividing both sides by 3 we get,
f ≤ 5, So Brittney can buy no more than 5 fishes.

Question 13.
Isaac has a bag of n peanuts. He shares the peanuts with 5 of his friends.
Each person gets at least 18 peanuts. The inequality 18 ≤ n ÷ 6
represents this situation. Graph the solution of this inequality.
Answer:
The number of peanuts Isaac has a bag of at least 108,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-42

Explanation:
Given Isaac has a bag of n peanuts. He shares the peanuts with 5 of his friends.
Each person gets at least 18 peanuts. The inequality 18 ≤ n ÷ 6
represents this situation. So the number of peanuts Isaac have are
6 X 18 ≤ 6 X n ÷ 6, multiplying the inequality both sides by 6,
108 ≤ n or n ≥ 108, so the graph of the solution
108 ≤ n or n ≥ 108 is as shown above.

Question 14.
a. Solve the inequality – 3x < 12.
b. Reasoning
Describe how you know the direction of the inequality sign
without solving the inequality.
Answer:
a. x > -4,
b. The inequality sign changes because of the
negative integer in the variable,

Explanation:
a. Given to solve the inequality -3x < 12,
-3x ÷ -3< 12 ÷ -3, dividing both sides by -3 and
reverse the inequality symbol,
x > -4.
b. The inequality sign can be determined without solving
because there is negative integer in the variable.
With the negative integer, automatically the inequality sign
changes.

Question 15.
Higher Order Thinking Renata and her family go through an
average of more than 15 cans of sparkling water each day.
They buy cases of 24 cans at $3.50 a case.
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.17
a. Write an inequality for the number of cases they go through in 30 days.
b. Solve the inequality in part a. If they buy only full cases,
how much do they spend on sparkling water in 30 days?
Answer:
a. x ≥ 18.75 is the inequality for the number of cases
they go through in 30 days,
b. $66.50 they spend on sparkling water in 30 days,

Explanation:
Given Renata and her family go through an
average of more than 15 cans of sparkling water each day.
They buy cases of 24 cans at $3.50 a case.
a.
1 day = 15 cans and 24 cans = $3.50,
So let x be number of cases
30 multiply 15 ÷ 24 = 18.75 almost 19,
therefore x ≥ 18.75 is the inequality for the
number of cases they go through in 30 days,
b. 19 X 3.5 = $66.50 they spend on sparkling water in 30 days.

Question 16.
Solve the inequality. Graph the solution on the number line.
-6.25x > -38\(\frac{3}{4}\)
Envision Math Common Core 7th Grade Answers Topic 5 Solve Problems Using Equations and Inequalities 8.18
Answer:
x < 6.2,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-43
Explanation:
Given to solve the inequality -6.25x > -38\(\frac{3}{4}\),
converting the mixed number to decimal before solving the inequality,
-38\(\frac{3}{4}\) = -38.75,
-6.25x > -38.75,
-6.25x ÷ -6.25 > -38.75 ÷ -6.25, dividing both sides by -6.25 and
reverse the inequality symbol,
x < 6.2, the graph of the solution x < 6.2 is shown above.

Assessment Practice

Question 17.
Cynthia plans to build a tree house that is \(\frac{1}{3}\) the
size of Andrew’s tree house. Cynthia plans to make the area of her
tree house at least 13 square feet.
PART A
Write and solve an inequality to find the area of Andrew’s tree house.
Let x be the area of Andrew’s tree house.
Answer:
\(\frac{1}{3}\)x ≥ 13,

Explanation:
Given Cynthia plans to build a tree house that is \(\frac{1}{3}\) the
size of Andrew’s tree house. Cynthia plans to make the area of her
tree house at least 13 square feet.
The inequality for the given situation is \(\frac{1}{3}\)x ≥ 13,
Now solving 3 X \(\frac{1}{3}\)x ≥ 3 X 13,
multiplying both sides by 3 we get
x ≥ 39 is the area of Andrew’s tree house.

PART B
Describe how you know which tree house is larger without solving the inequality.
Answer:
It is because of the factor that was multiplied to the
area of the Andrew’s tree house which is less than 1,

Explanation:
Since the factor that was multiplied to the
area of the Andrew’s tree house which is less than 1,
it can be easily be determined that Cynthia’s tree house is
smaller than Andrew’s tree house.

3-ACT Math

Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.19

ACT 1

Question 1.
After watching the video, what is the first question that comes to mind?
Answer:

Question 2.
Write the Main Question you will answer.
Answer:

Question 3.
Construct Arguments Make a prediction to answer this Main Question. Explain your prediction.

Question 4.
On the number line below, write a number that is too small to be the answer. Write a number that is too large. Too small
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.20
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.21
Answer:

Question 5.
Plot your prediction on the same number line.
Answer:

ACT 2

Question 6.
What information in this situation would be helpful to know? How would you use that information?
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.22
Answer:

Question 7.
Use Appropriate Tools What tools can you use to solve the problem?
Explain how you would use them strategically
Answer:

Question 8.
Model with Math Represent the situation using mathematics.
Use your representation to answer the Main Question.
Answer:

Question 9.
What is your answer to the Main Question? Is it higher or lower than your initial prediction? Explain why.
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.23
Answer:

ACT 3

Question 10.
Write the answer you saw in the video.
Answer:

Question 11.
Reasoning Does your answer match the answer in the video? If not, what are some reasons that would explain the difference?
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.24
Answer:

Question 12.
Make Sense and Persevere Would you change your model now that you know the answer? Explain.
Answer:

Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.25

ACT 3

Extension

Reflect

Question 13.
Model with Math Explain how you used a mathematical model to represent the situation.
How did the model help you answer the Main Question?
Answer:

Question 14.
Reasoning If all single tracks were on sale for 10% off, how would your model change?
How would the answer to the Main Question change?
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.26
Answer:

SEQUEL

Question 15.
Make Sense and Persevere Suppose you have a $50 gift card to the same site.
You want to buy an album with 16 tracks for $12.99 and then use the rest of the
gift card for single tracks. How many songs can you buy with the gift card?
Answer:

Lesson 5.6 Solve Two-Step Inequalities

Solve & Discuss It!

Rico and Halima are shopping for craft sticks, glue, and electrical tape for a science project.
Together, they have $30 to spend on supplies.
How should they spend their $30 if they need at least 1,000 craft sticks?
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.27

Focus on math practices
Make Sense and Persevere At the store, Rico and Halima find
boxes of 500 craft sticks for $7.50.
Which boxes of craft sticks should they buy?
Answer:
Rico and Halima should buy the box with 500 craft sticks,

Explanation:
Rico and Halima should buy the box with 500 craft sticks,
buying 2 boxes of 500 craft sticks will give them a total
of 1000 craft sticks at a lower price which will cost them $15,
instead of buying at least 4 boxes of 275 craft sticks.

Essential Question
How is solving a two-step inequality similar to and different from solving a two-step equation?
Answer:
Equations and Inequalities – Two-step equations and inequalities –
It takes two steps to solve an equation or inequality that has more than one operation:
Simplify using the inverse of addition or subtraction. Simplify further by using
the inverse of multiplication or division.

Explanation:
It takes two steps to solve an equation or inequality that has more than one operation:
Simplify using the inverse of addition or subtraction.
Simplify further by using the inverse of multiplication or division.
when you multiply or divide an inequality by a negative number,
we must reverse the inequality symbol.

Try It!

Erin has $52 to spend at the florist. She wants to buy a vase for $11.75 and
several roses for $3.50 each. What are the possible numbers of roses Erin can buy?
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 8.28
Answer:
Erwin can buy up to 11 roses,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-44

Explanation:
Given Erin has $52 to spend at the florist. She wants to buy a vase for $11.75 and
several roses for $3.50 each. The possible numbers of roses Erin can buy are
11.75 + 3.50r ≤ 52,
11.75 + 3.50r – 11.75 ≤ 52 – 11.75, subtracting 11.75 from both sides,
3.50r ≤ 40.25,
3.50r  ÷ 3.50 ≤ 40.25  ÷ 3.50, dividing both sides by 3.50 we get
r ≤ 11.50, therefore Erwin can buy up to 11 roses.

Convince Me!
What properties did you use to solve the inequality? 300 5-6 Solve Two-Step Inequalities.
Answer:
Subtraction property,
Division property.

Explanation:
Solving two-step inequalities,
Example:
x + 8 > 5,
Isolated the variable x by subtracting 8 from both sides of the inequality.
x + 8 – 8 > 5 – 8 => x > −3, Therefore, x > −3.

Try It!

The Jazz Band needs to raise at least $600 to travel to an upcoming competition.
The members of the band have already raised $350. If they sell calendars for $8 each,
how many calendars would they need to sell to exceed their goal?
Answer:
Jazz band needs to sell at least 32 calendars to exceed their goal,

Explanation:
Given the Jazz Band needs to raise at least $600 to travel to an upcoming competition.
The members of the band have already raised $350. If they sell calendars for $8 each,
number of calendars would they need to sell to exceed their goal if x is the
number of calendars,
350 + 8x ≥ 600,
350 + 8x – 350 ≥ 600 -350, subtracting 350 from both sides,
8x ≥ 250,
8x ÷ 8 ≥ 250 ÷ 8, dividing both sides by 8,
x ≥ 31.25, therefore, Jazz band needs to sell at least 32 calendars to exceed their goal.

Try It!
Solve the inequality 5 – \(\frac{1}{2}\)x > 30.
Answer:
x < -50,

Explanation:
Given the inequality 5 – \(\frac{1}{2}\)x > 30,
5 – \(\frac{1}{2}\)x -5 > 30 – 5, subtract 5 from both the sides,
–\(\frac{1}{2}\)x  > 25,
-2 X – \(\frac{1}{2}\)x > -2 X 25, multiplying both sides by -2 and reverse
the inequality symbol as x < -50.

KEY CONCEPT

Like two-step equations, solving two-step inequalities involves carrying out
two different operations—addition or subtraction, and multiplication or division.
Unlike two-step equations, which have a single solution,
two-step inequalities have multiple solutions.

Do You Understand?

Question 1.
Essential Question How is solving a two-step inequality similar to and
different from solving a two-step equation?
Answer:
The similarity between the two is that they are carrying out two
different operations,
The difference is that the number of solutions they have,

Explanation:
The similarity between solving a two-step inequality and
two-step equation is that they are carrying out two
different operations,
The difference between solving a two-step inequality and
two-step equation is that two-step equation only have
single solution unlike two-step inequalities have multiple solutions.

Question 2.
Reasoning What is the difference between the number of solutions for
a two-step equation and for a two-step inequality?
Answer:
Two-step equations only have a single solution,
Two-step inequalities have multiple solutions,

Explanation:
Two-step equations there is only a single solution,
Two-step inequalities there are multiple solutions,
this is because of the inequality symbol, which makes
the inequality true for as long as the value of the variable
is within the given solution.

Question 3.
Why are inverse relationships between operations used to solve two-step inequalities?
Answer:
Inverse relationships between operations are used to isolate the variable on the one side
of the inequality,

Explanation:
Inverse relationships between operations are used to solve two-step inequalities
in order to isolate the variable on the one side of the inequality, removing the
values together with the variable means that the inverse operation should be used
on both sides.

Do You Know How?

Question 4.
Joe ran 3 miles yesterday and wants to run at least 12 miles this week.
Write an inequality that can be used to determine the additional number
of days Joe must run this week if each run is 3 miles. Then solve the inequality.
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 10.1
Answer:
The inequality for the given situation is 3 + 3x  ≥ 12,
Joe need to run at least 3 days to meet his target,

Explanation:
Given Joe ran 3 miles yesterday and wants to run at least 12 miles this week.
Let x be number of days Joe must run this week if each run is 3 miles.
The inequality for the given situation is 3 + 3x  ≥ 12,
3 + 3x -3 ≥ 12 -3, subtracting 3 both sides,
3x  ≥ 9, dividing both sides by 3 we get
x  ≥ 3, therefore, Joe need to run at least 3 days to meet his target.

Question 5.
Solve 4 + 6.5x < 36.5.
Answer:
Solving 4 + 6.5x < 36.5, we get x < 5,

Explanation;
Given the inequality 4 + 6.5x < 36.5,
4 + 6.5x -4 < 36.5 -4, subtracting 4 from both the sides,
6.5x < 32.5,
6.5x ÷ 6.5 < 32.5 ÷ 6.5, dividing both sides by 6.5,
x < 5.

Question 6.
Tomas has $1,000 to spend on a vacation. His plane ticket costs $348.25.
If he stays 5.5 days at his destination, how much can he spend each day?
Write an inequality and then solve.
Answer:
Inequality: 348.25 + 5.5x ≤ 1000,
Tomas can spend no more than $118.50 per day,

Explanation:
Given Tomas has $1,000 to spend on a vacation. His plane ticket costs $348.25.
If he stays 5.5 days at his destination let x be the amount,
the inequality for the given situation is 348.25 + 5.5x ≤ 1000,
348.25 + 5.5x – 348.25 ≤ 1000 – 348.25, subtracting 348.25 from both the sides,
5.5x ≤ 651.75,
5.5x ÷ 5.5 ≤ 651.75 ÷ 5.5, dividing both sides by 5.5,
x ≤ 118.50, therefore, Tomas can spend no more than $118.50 per day.

Question 7.
Solve 12 – \(\frac{3}{5}\)x > 39.
Answer:
Solving 12 – \(\frac{3}{5}\)x > 39, we get x < -45,

Explanation:
Given 12 – \(\frac{3}{5}\)x > 39,
12 – \(\frac{3}{5}\)x – 12 > 39 – 12, subtracting 12 from both sides,
– \(\frac{3}{5}\)x > 27,
– 5 X- \(\frac{3}{5}\)x < – 5 X 27, multiplying both sides by -5 and
reverse the inequality symbol,

3x < -135,
3x ÷ 3 < -135 ÷ 3, divide both sides by 3,
x < -45.

Practice & Problem Solving

Leveled Practice For 8 and 9, fill in the boxes to write and solve each inequality.

Question 8.
Eight less than the product of a number n and \(\frac{1}{5}\) is no more than 95.
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 10.10
Answer:
n ≤  515,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-45

Explanation:
The inequality is \(\frac{1}{5}\) x – 8 ≤ 95,
\(\frac{1}{5}\) x – 8 + 8 ≤ 95 +8, adding 8 on both  sides,
\(\frac{1}{5}\) x ≤ 103,
5 X \(\frac{1}{5}\) x ≤ 5 X 103, multiplying both sides by 5,
x ≤ 515.

Question 9.
Seven more than the quotient of a number b and 45 is greater than 5.
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 10.11
Answer:
b > -90,
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-46
Explanation:
Given \(\frac{b}{45}\) + 7 > 5,
\(\frac{b}{45}\) + 7  – 7 > 5 – 7, subtracting 7 from both sides
\(\frac{b}{45}\)  > -2,
45 X \(\frac{b}{45}\) > 45 X (-2), multiplying both sides by 45 we get,
b > -90.

Question 10.
Solve the inequalities and compare.
a. Solve 2x + 6 < 10.
b. Solve -2x + 22 < 18.
c. Which is the correct comparison of solutions for
2x + 6 < 10 and -2x + 22 < 18?
A. The inequalities have some common solutions.
B. The inequalities have one common solution.
C. The inequalities have no common solutions.
D. The inequalities have the same solutions.
Answer:
a. x < 2,
b. x > 2,
c. C. The inequalities have no common solutions,

Explanation:
a. Solving 2x + 6 < 10,
2x + 6 -6 < 10 -6, subtracting 6 from both sides,
2x < 4,
2x ÷ 2 < 4 ÷ 2, dividing both sides by 2,
so x < 2,
b. Solving -2x + 22 < 18,
-2x +22 -22 < 18 -22, subtracting 22 from both sides,
-2x < -4,
-2x ÷ -2 > -4 ÷ -2, dividing both sides by -2 and reverse the inequality symbol,
so x > 2,
c. The  correct comparison of solutions for the two given
inequalities 2x + 6 < 10 and -2x + 22 < 18 are
the inequalities have no common solutions, the first inequality
has a solution that the value of x should be less than 2 to make the
inequality true, the second inequality has a solution that the value of
x should be greater than 2.

Question 11.
Make Sense and Persevere Talia has a daily budget of $94 for a car rental.
Write and solve an inequality to find the greatest distance Talia can drive
each day while staying within her budget.
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 11.1
Answer:
Tali can drive no more than 320 miles,

Explanation:
Let x be the distance per mile,
The inequality for the given situation is 30 + 0.20x ≤ 94,
solving 30 + 0.20x ≤ 94,
30 + 0.20x -30 ≤ 94 -30, subtracting 30 from both sides,
0.20 x ≤ 64,
0.20 x ÷0.20 ≤ 64 ÷ 0.20,dividing both sides by 0.20
x ≤ 320, therefore, Tali can drive no more than 320 miles.

Question 12.
Model with Math A manager needs to rope off a
rectangular section for a private party. The length of
the section must be 7.6 meters. The manager can use
no more than 28 meters of rope. What inequality could
you use to find the possible width, w, of the roped-off section?
Answer:
Inequality:
2(7.6) + 2(w) ≤ 28,
The width of the roped – off section should be no
more than 6.4 meters,

Explanation:
Given A manager needs to rope off a
rectangular section for a private party. The length of
the section must be 7.6 meters. The manager can use
no more than 28 meters of rope. The inequality to find
the possible width, w, of the roped-off section is 2(7.6) + 2(w) ≤ 28,
15.2 + 2w ≤ 28, multiplying the values,
15.2 + 2w – 15.2 ≤ 28 – 15.2, substracting 15.2 from both sides,
2w ≤ 12.8,
2w ÷ 2 ≤ 12.8 ÷ 2, dividing both sides by 2,
w ≤ 6.4 , therefore, the width of the roped – off section should be no
more than 6.4 meters.

Question 13.
Higher Order Thinking Andrea went to the store to buy a
sweater that was on sale for 40% off the original price.
It was then put on clearance at an additional 25% off the sale price.
She also used a coupon that saved her an additional $5.
Andrea did not spend more than $7.60 for the sweater.
What are the possible values for the original price of the sweater?
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 11.2
Answer:
The price of the sweater is no more than $28,

Explanation:
Given Andrea went to the store to buy a
sweater that was on sale for 40% off the original price.
It was then put on clearance at an additional 25% off the sale price.
She also used a coupon that saved her an additional $5.
Andrea did not spend more than $7.60 for the sweater.
Let x be the original price of the sweater so the inequality
is 0.75(0.6x) – 5 ≤ 7.6, multiplying the values
0.75(0.6x) – 5 ≤ 7.6, adding 5 both sides,
0.45 x – 5 + 5  ≤ 7.6 + 5,
0.45x ≤ 12.6,
0.45x ÷ 0.45 ≤ 12.6 ÷ 0.45, dividing both sides by 0.45,
x ≤ 28, the price of the sweater is no more than $28.

Question 14.
A pool can hold 850 gallons. It now has 598 gallons of
water and is being filled at the rate shown.
How many more minutes, m, can water continue to
flow into the pool before it overflows? Write and solve an inequality.
Envision Math Common Core Grade 7 Answers Topic 5 Solve Problems Using Equations and Inequalities 11.3
Answer:
Inequality :
598 + 15.75m ≤ 850,
The water can  continue to flow into the pool before it overflows
no more 16 minutes,

Explanation:
Given A pool can hold 850 gallons. It now has 598 gallons of
water and is being filled at the rate shown. So more minutes, m,
can water continue to flow into the pool before it overflows is
solving the inequality 598 + 15.75m ≤ 850,
598 + 15.75m – 598 ≤ 850 – 598, subtracting 598 from both sides,
15.75m ≤ 252,
15.75m ÷15.75 ≤ 252 ÷ 15.75, dividing both sides by 15.75 we get
m ≤ 16, therefore the water can  continue to flow into the pool
before it overflows no more 16 minutes.

Assessment Practice

Question 15.
Use the rectangle diagram at the right.
PART A
Write and solve an inequality to find the values of x for
which the perimeter of the rectangle is less than 120.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 11.33
Answer:
Inequality:
2(x + 4) + 2x < 120,
x < 28,

Explanation:
Given length of rectangle x + 4 and breadth as x and
for which the perimeter of the rectangle is less than 120,
The inequality for the given situation is 2(x + 4) + 2x < 120,
2x + 8 +2x < 120, using distributive property,
4x + 8 < 120, combining like terms,
4x + 8 – 8 < 120 – 8, subtracting 8 from both sides,
4x < 112,
4x ÷ 4 < 112 ÷ 4, dividing both sides by 4 we get
x < 24.

PART B
Based on your answer to Part A, are there any values that
can be eliminated from the solution set? Explain.
Answer:
Yes, 28 can be eliminated from the solution set,

Explanation:
There is a value that can be eliminated in the solution set,
28 is not part of the solution set since the solution set is
less than 28, it means any value that is 27 or below.

Question 16.
Kari is building a rectangular garden bed. The length is 6 feet.
She has 20 feet of boards to make the sides.
Write and solve an inequality to find the possible width of her garden bed.
Answer:
2(6 + w) ≤ 20,
The width of Kari garden bed is less than 4,

Explanation:
Given Kari is building a rectangular garden bed. The length is 6 feet.
She has 20 feet of boards to make the sides.
Let w be the possible width of her garden bed.
The inequality is 2(6 + w) ≤ 20,solving for w,
2(6 + w) ≤ 20, multiplying the values,
12 + 2w ≤ 20, subtracting 12 both sides,
12 + 2w -12 ≤ 20 -12, subtracting 12 both sides,
2w ≤ 8,
2w ÷ 2 ≤ 8 ÷ 2, dividing both sides by 2,
w ≤ 4, therefore the width of Kari garden bed is less than 4.

Lesson 5.7 Solve Multi-Step Inequalities

Explore It

Charlene has 2 flash drives of the same size that
she uses to store pictures and videos. Each drive is
holding the same number of GB of data, d.
She wants to move everything to a memory card that can hold up to 8 GB.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 12.1

A. Charlene is going to delete 1 GB of data from each flash drive.
How can the total amount of data left on the two flash drives be
represented as an expression?
B. How can the expression you wrote be used to
write an inequality that shows the maximum amount of
data each flash drive can have on it in order to have all
the data transfer to the 8 GB memory card?
Answer:
a. 2(d – 1),
b. 2(d – 1) ≤ 8,

Explanation:
Given Charlene has 2 flash drives of the same size that
she uses to store pictures and videos. Each drive is
holding the same number of GB of data, d.
She wants to move everything to a memory card that can hold up to 8 GB.
a. Charlene is going to delete 1 GB of data from each flash drive.
So the total amount of data left on the two flash drives be
represented as an expression as 2(d – 1).
b. The expression I wrote can be used
for the inequality that shows the maximum amount of
data each flash drive can have on it in order to have all
the data transfer to the 8 GB memory card is 2(d – 1) ≤ 8.

Focus on math practices
Reasoning If each flash drive has 5 GB of memory, can all of
the data be transferred to the memory card? Explain.
Answer:
A flash drive has 5 GB of memory, can have all of its
data be transferred to the memory card,

Explanation:
Using the inequality to determine If each flash drive
has 5 GB of memory can be transferred to the memory card so
2(d – 1) ≤ 8,
2d – 2 ≤ 8, applying distributive property,
2d – 2 + 2 ≤ 8 + 2, adding 2 on both sides,
2d ≤ 10,
2d ÷ 2 ≤ 10 ÷ 2, dividing both sides by 2,
d ≤ 5,
From the solution set, a flash drive can hold no more than
5 GB, therefore, a flash drive has 5 GB of memory,
can have all of its data be transferred to the memory card.

Essential Question
How is solving a multi-step inequality similar to and different
from solving a multi-step equation.
Answer:
Two are similar because of the methods used in solving,
The difference between the two is the number of solution,

Explanation:
Solving a multi-step inequality and solving a multi-step equation is similar
because of the methods used in solving like using the Distributive Property,
combining like terms and use inverse relationships and properties to solve them.
The difference between a multi-step inequality and solving a multi-step equation is
the number of solution. For multi-step equation there is one possible solution,
for multi-step inequality there are many possible solutions.

Try It!

Twice the difference of Felipe’s age, f, and 4 is at least 2.
What are possible values for Felipe’s age? Graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 12.5

Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-47
Explanation:
Given twice the difference of Felipe’s age, f, and 4 is at least 2,
the possible values for Felipe’s age are inequality 2(f-4) ≥ 2,
2f – 8 ≥ 2, used distributive property,
2f – 8 + 8 ≥ 2 + 8, adding 8 on both sides,
2f ÷ 2 ≥ 10 ÷ 2, dividing both sides by 2,
f ≥ 5, so the graph of the solution f ≥ 5 is as shown above.

Convince Me!
Describe the similarity between the process of solving an inequality with two steps and
solving an inequality with more than two steps.

Try It!
Solve the inequality – 1 – 6(6 + 2x) < 11. Then graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 12.6
Solve the inequality 3(4 – 6) + 2 ≥ 2(-t + 3) + 4. Then graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 12.7
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-48
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-49
Explanation:
Solving the inequality – 1 – 6(6 + 2x) < 11,
-1 -36 -12x < 11, used distributive property,
-37 -12x < 11, combining like terms,
-37 -12x + 37 < 11 + 37, Adding 37 on both sides,
-12x > 48,
-12x ÷ 12 > 48 ÷ 12, dividing both sides by -12 and reverse inequality symbol,
x > 4, so the graph of the solution x > 4 is as shown above.

Solving the inequality 3(4 – 6) + 2 ≥ 2(-t + 3) + 4,
12 – 18 + 2 ≥ -2t + 6 + 4, used distributive property,
-4 ≥ -2t + 10, combining like terms,
-4 – 10 ≥ -2t + 10 – 10, subtracting 10 from both sides,
-14 ≥ -2t,
-14 ÷ -2 ≤ -2t ÷ -2, dividing both sides by -2 and reverse inequality symbol,
7 ≤ t, so the graph of the solution 7 ≤ t is as shown above.

KEY CONCEPT

Solving multi-step inequalities is similar to solving multi-step equations.
You may need to use the Distributive Property, combine like terms, and
use inverse relationships and properties to solve them.
4(y – 4) + 8 ≤ 20
4y – 16 + 8 ≤ 20
4y – 8 ≤ 20
4y – 8 + 8 ≤ 20 + 8
4y ≤ 28
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 12.8

Do You Understand?

Question 1.
Essential Question How is solving a multi step inequality similar to and
different from solving a multi-step equation?
Answer:
Two are similar because of the methods used in solving,
The difference between the two is the number of solution,

Explanation:
Solving a multi-step inequality and solving a multi-step equation is similar
because of the methods used in solving like using the Distributive Property,
combining like terms and use inverse relationships and properties to solve them.
The difference between a multi-step inequality and solving a multi-step equation is
the number of solution. For multi-step equation there is one possible solution,
for multi-step inequality there are many possible solutions.

Question 2.
Be Precise Explain how you would combine like terms and use properties of
operations to solve the inequality 5(2t + 3) – 3t < 16.
Answer:
t < 1/7,

Explanation:
Given to solve the inequality 5(2t + 3) – 3t < 16,
10t + 15 – 3t <16, used distributive property,
7t + 15 < 16, combining like terms,
7t + 15 -15 < 16 – 15, subtracting 15 from both sides of the inequality,
7t < 1,
7t ÷ 7 < 1 ÷7, dividing both sides by 7 we get,
t < 1/7.

Question 3.
Critique Reasoning Gloria’s solution to a multi-step inequality is r> 7.
She states that the graph will have an open dot at 7 and extend with
an arrow to the right indefinitely. Is she correct? Explain.
Answer:
Gloria’s describes the solution correctly,

Explanation:
Gloria is correct because it will open dot as the solution does not
include 7 as the part of the solution, the inequality symbol is greater
than which means that the arrow will extend to the right.

Do You Know How?

Question 4.
Solve the inequality 2(n + 3) – 4 < 6. Then graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.1
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-50

Explanation:
Given 2(n + 3) – 4 < 6,
2n + 6 – 4 < 6, using distributive property,
2n + 2 < 6, combined like terms,
2n + 2 – 2 < 6 – 2, subtracting 2 from both sides,
2n < 4,
2n ÷ 2 < 4 ÷ 2, dividing both sides by 2,
n < 2, so the graph of the solution n < 2 is as shown above.

Question 5.
Solve the inequality -2(x + 3) + 2 ≥ 6. Then graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.2
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-51

Explanation:
Given -2(x + 3) + 2 ≥ 6,
-2x – 6 + 2 ≥ 6, using distributive property,
-2x – 4 ≥ 6, combined like terms,
-2x – 4 + 4 ≥ 6 + 4, adding 4 on both sides,
-2x ≥ 10,
-2x ÷ -2 ≤ 10 ÷ -2, dividing both sides by -2 and reversing inequality symbol,
x ≤ 5, so the graph of the solution x ≤ 5 is as shown above.

Question 6.
Three times the difference of Federico’s age and 4, increased by 7, is greater than 37.
What are possible values of Federico’s age? Graph his possible ages on the number line.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.3
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-52

Explanation:
Given three times the difference of Federico’s age and 4, increased by 7
is greater than 37. The possible values of Federico’s age are
3(x – 4) + 7 > 37,
3x – 12 + 7 > 37, using distributive property,
3x – 5 > 37, combined like terms,
3x – 5 + 5 > 37 + 5, adding 5 on both sides,
3x > 42,
3x ÷ 3 > 42 ÷ 3, dividing both sides by 3,
x > 14, so there Federico’s age should be greater than 14,
The graph of the possible ages of Federico’s is as shown above.

Practice & Problem Solving

Question 7.
Use the inequality 18 < -3(4x – 2).
a. Solve the inequality for x.
b. Which graph shows the solution to the inequality?
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.4
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-53
Explanation:
a. Given to solve the inequality 18 < -3(4x -2),
18 < -12x + 6, using distributive property,
18 – 6 < -12x + 6 – 6, subtracting 6 from both sides,
12 < -12x,
12 ÷ -12 > -12x ÷ -12, dividing both sides by -12 and reversing inequality symbol,
-1 > x,
b. Graph A shows the solution to the inequality 18 < -3(4x -2) as -1 > x which
is shown above.

Question 8.
Michelle says that the solution to the inequality 2(4y – 3) > -22 is y> -3.5.
Her work is shown.
2(4y – 3) > -22
8y > -28
y > -3.5
a. What was Michelle’s mistake?
b. What is the solution to the inequality?
Answer:
a. Michelle did not use the inverse relationship in order to isolate the variable,
b. The solution is y > -2,

Explanation:
a. After using distributive property, Michelle did not use the inverse relationship
in order to isolate the variable, she thought that subtracting 6 on the right side of inequality
will remove the 6 as well on left side of the inequality,
b. Solving the inequality 2(4y – 3) > -22,
8y – 6 > -22, using distributive property,
8y – 6 + 6 > -22 + 6, adding 6 on both sides,
8y > -16,
8y ÷ 8 > -16 ÷ 8, dividing both sides by 8 we get
y > -2.

Question 9.
Model with Math The length of a picture frame is 7 inches more than the width.
For what values of x is the perimeter of the picture frame greater than 154 inches?
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.5
Answer:
The width of the picture frame is greater than 35 inches,

Explanation:
Given the length of a picture frame is 7 inches more than the width.
So the values of x for which the perimeter of the picture frame will be
greater than 154 inches is
2(x + 7) + 2 (x) > 154,
2x + 14 + 2x > 154, using distributive property,
4x + 14 > 154, combined like terms,
4x + 14 – 14 > 154 – 14, subtracting 14 on both sides,
4x > 140,
4x ÷ 4 > 140 ÷ 4, dividing both sides by 4 we get
x > 35, therefore the width of the picture frame is greater than 35 inches.

Question 10.
Critique Reasoning Sierra says that she can simplify the left side of
the inequality 2(-3 + 5) + 2 ≥ -4(x – 2) – 3 by combining the terms
within the parentheses, but that she can’t do the same on the right side.
Is Sierra correct? Explain.
Answer:
Sierra is correct about combining the terms,

Explanation:
Sierra is correct as the terms inside the parentheses are both constant,
Performing the operation inside the parentheses can combine
the two constants. She is also correct that on the right side of inequality,
the term are not the same, therefore it cannot be combined.

Question 11.
a. Solve the inequality 30 ≥ 6(\(\frac{2}{3}\)z + \(\frac{1}{3}\)).
b. Solve the inequality 15.6 < 2.7(z – 1) – 0.6.
c. Are there any values of z that solve both inequalities?
Use a number line to support your answer.
Answer:
a. 7 ≥ z,
b. 7< z,
c. Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-54

Explanation:
a. Solving the inequality 30 ≥ 6(\(\frac{2}{3}\)z + \(\frac{1}{3}\)),
30 ≥ 4z + 2, using distributive property,
30 – 2 ≥ 4z + 2 – 2, subtracting 2 on both sides,
28 ≥ 4z,
28 ÷ 4 ≥ 4z ÷ 4, dividing both sides by 4 we get 7 ≥ z.

b. Solving the inequality 15.6 < 2.7(z – 1) – 0.6,
15.6 < 2.7z – 2.7 – 0.6, using distributive property,
15.6 < 2.7z – 3.3, combined like terms,
15.6 + 3.3 < 2.7z – 3.3 + 3.3, adding 3.3 on both sides,
18.9 < 2.7z,
18.9 ÷ 2.7 < 2.7z ÷ 2.7, dividing both sides by 2.7,
we get 7 < z.

c. There are no values that could solve both inequalities,
This is because, the first inequality has the solution set of any
value no more than 7 while the second inequality has the solution
set of any value greater than 7. The solution of first inequality, includes
7 while the solution for the second inequality does not include 7.

Question 12.
Mr. Lin baked banana bread for a bake sale to raise money for the math team.
He said that he added a spoonful of walnuts for each of the students in
his three classes, and that he added more than 250 walnuts. He used the
inequality 16W + 24W + 10w > 250 to represent the situation, where w represents
the number of walnuts in each spoonful. How many walnuts could be in each spoonful?
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.6
Answer:
Each spoonful have greater than 5 walnuts,

Explanation:
Given Mr. Lin baked banana bread for a bake sale to raise money for the math team.
He said that he added a spoonful of walnuts for each of the students in
his three classes and that he added more than 250 walnuts. He used the
inequality 16W + 24W + 10w > 250 to represent the situation, where w represents
the number of walnuts in each spoonful. So number of many walnuts could be in
each spoonful is writing inequality 16W + 24W + 10w > 250 and solving as
50w > 250, combining like terms,
50w ÷ 50 > 250 ÷ 50, dividing both sides by 50,
we get w >5, therefore, each spoonful have greater than 5 walnuts.

Question 13.
Use both the Addition and Multiplication Properties of Inequality
to solve the inequality.
Graph the solutions on a number line. 2(3y – 5) < -16
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.7
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-55

Explanation:
Solving the inequality 2(3y – 5) < -16,
6y – 10 < -16, using distributive property,
6y – 10 + 10 < -16 + 10, adding 10 on both sides,
6y < -6,
6y ÷ 6 < -6 ÷ 6, dividing both sides by 6,
we get y < -1.

Question 14.
Higher Order Thinking Solve each of the given inequalities for z.
Which of the inequalities has 5 as a solution?
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 13.8
Answer:
The inequality that has a solution of 5 is Inequality 1,

Explanation:
Given to solve the inequality 4(2.8z +1.75) > -26.6,
11.2z + 7 > -26.6, using distributive property,
11.2z + 7 – 7 > -26.6 – 7, subtracting 7 on both sides,
11.2z > -33.6,
11.2z ÷ 11.2 > -33.6 ÷ 11.2, dividing both sides by 11.2,
z > -3,
Given to solve the inequality 2(1.9z +1.5) ≤ 18.2,
3.8z + 3 ≤ 18.2, using distributive property,
3.8z + 3 – 3 ≤ 18.2 – 3 subtracting 7 on both sides,
3.8z ≤ 15.2,
3.8z ÷ 3.8 ≤ 15.2 ÷ 3.8, dividing both sides by 3.8,
z ≤ 4,
So the inequality that has a solution of 5 is Inequality 1.

Assessment Practice

Question 15.
The school band needs $500 to buy new hats. They already have $200.
They are selling bumper stickers for $1.50 each.
How many bumper stickers do they need to sell to have
at least $500? Write and solve an inequality that represents the situation.
Answer:
200 bumper stickers do they need to sell,
Inequality : 1.50b + 200 = 500,

Explanation:
Given the school band needs $500 to buy new hats. They already have $200.
They are selling bumper stickers for $1.50 each.
Let b be the number of  bumper stickers do they need to sell to have
at least $500? The inequality that represents the situation is
1.50b + 200 ≤ 500, solving,
1.50b + 200 – 200 ≤ 500 – 200, subtracting 200 both sides,
1.50b ≤ 300,
1.50b ÷1.50 ≤ 300 ÷ 1.50, dividing both sides by 1.50,
b ≤ 200, therefore 200 bumper stickers do they need to sell and
Inequality : 1.50b + 200 = 500.

Topic 5 REVIEW

Topic Essential Question

How can you solve real-world and mathematical problems with numerical and
algebraic equations and inequalities?
Answer:
Through the use of equations and inequalities , we will be able to determine
the possible solutions to the problem,

Explanation:
Real world and mathematical problems can be solved through the use
of numerical and algebraic equations and inequalities.
In a certain problem there are unknown that needs to be solved.
Therefore, using equations and inequalities in order to determine
the unknown it will help to easily solve the problem.
Through the use of equations and inequalities we will be
able to determine the possible solutions to the problem.

Vocabulary Review

Complete each definition and then provide an example of each vocabulary word used.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 20.1

Question 1.
You Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 20.2 when you divide both sides of the equation 3n = 12 by 3.
Answer:
Isolate the variable,
When we divide both sides of the equation 3n = 12 by 3, we isolate
the variable,

Explanation:
3n = 12,
3n ÷ 3 = 12 ÷ 3, Dividing both sides by 3 we get n = 4.

Question 2.
A statement that contains >, <, ≥, ≤, or ≠ to compare two expressions is a(n)
Answer:
Inequality,

Explanation:
Inequality is a statement that contains >, <, ≥, ≤, or ≠ to compare two expressions.

Question 3.
You can use the Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 20.2 to remove parentheses in
the process of solving the equation – 10(x + 5) = 40.
Answer:
Distributive Property,

Explanation:
In the the process of solving the equation – 10(x + 5) = 40,
we use distributive property to remove parentheses as
-10x -50 = 40.

Use Vocabulary in Writing
Write an equation or inequality to represent the following situation:
17 is at least 5 more than 3 times x. Explain how you wrote your
equation or inequality. Use vocabulary from Topic 5 in your explanation.
Answer:
Equation or Inequality : 17 > 3x + 5,

Explanation:
Given the situation as 17 is at least 5 more than 3 times x,
So wrote the equation or inequality as 17 > 5 + 3x means
17 is greater than 5 and 3 times of x(3x), Vocabulary used is
equation or inequality.

Concepts and Skills Review

LESSONS 5-1 AND 5-2
Write Two-Step Equations | Solve Two-Step Equations

Quick Review
Equations can be used to represent situations. Two-step equations have two
different operations.
The properties of equality can be applied the same way when solving
two-step equations as when solving one-step equations.

Practice

Question 1.
The total number of students in the seventh grade is 9 more than 4 times
as many students as are in the art class. There are 101 students in the seventh grade.
Write and solve an equation to find the number of students in the art class.
Let x represent the number of students in the art class.
Answer:
Equation : 4x + 9 = 101,
There are 23 students in the art class,

Explanation:
Given the total number of students in the seventh grade is 9 more than 4 times
as many students as are in the art class. There are 101 students in the seventh grade.
Let x represent the number of students in the art class.
So the equation to find the number of students in the art class is  4x + 9 = 101, on solving
4x + 9 – 9 = 101 – 9, subtracting 9 from both sides,
4x ÷ 4 = 92 ÷ 4, Dividing both sides by 4 we get
x = 23, therefore there are 23 students in the art class,

Question 2.
List the steps to solve the following equation: 5x – 6 = 44.
Then solve for x.
Answer:
x = 10,

Explanation:
The steps to solve the following equation : 5x – 6 = 44 is
5x – 6 + 6 = 44 + 6, adding 6 on both sides,
5x = 50,
5x ÷ 5 = 50 ÷ 5, dividing both sides by 5 we get x = 10.

Question 3.
Solve for the given variable.
a. 4y + 3 = 19
b. \(\frac{1}{2}\)n – 3 = 5
Answer:
a. y = 4,
b. n = 16,

Explanation:
Solving:
a. 4y + 3 = 19,
4y + 3 – 3 = 19 – 3, subtracting 3 on both sides,
4y = 16,
4y ÷ 4 = 16 ÷ 4, dividing both sides by 4 we get y = 4.

b. \(\frac{1}{2}\)n – 3 = 5,
\(\frac{1}{2}\)n – 3  + 3 = 5 + 3, adding 3 on both sides,
\(\frac{1}{2}\)n = 8,
2 X \(\frac{1}{2}\)n = 2 X 8, multiplying both sides by 2 we get
n = 16.

LESSON 5.3 Solve Equations Using the Distributive Property

Quick Review
Use the Distributive Property to solve problems of the form p(x + q) = r.

Practice

Question 1.
There are 450 seats in the lower level of a concert hall with
b balcony seats in the upper level. So far, 170 tickets have been sold,
which is \(\frac{1}{5}\) of the total number of seats in the concert hall.
How many tickets sold are balcony seats?
Answer:
There are 400 balcony seats in the concert hall,

Explanation:
Given there are 450 seats in the lower level of a concert hall with
b balcony seats in the upper level. So far, 170 tickets have been sold,
which is \(\frac{1}{5}\) of the total number of seats in the concert hall.
Number of tickets sold which are balcony seats are
Equation: \(\frac{1}{5}\)(b + 450) = 170,
\(\frac{1}{5}\)b + 90 = 170, Using distributive property,
\(\frac{1}{5}\)b + 90 – 90 = 170 – 90, subtracting 90 from both sides,
\(\frac{1}{5}\)b = 80,
5 X \(\frac{1}{5}\)b = 5 X 80 , multiplying both sides by 5 we get
b = 400, therefore there are 400 balcony seats in the concert hall.

Question 2.
Solve the equation -4(8 + y) = 90.
Answer:
y = -30.5,

Explanation:
Given to solve -4(8 + y) = 90,
-32 – 4y = 90, Using distributive property,
-32 – 4y + 32 = 90 + 32, adding 32 on both sides,
-4y = 122,
-4y ÷ -4 = 122 ÷ -4, dividing both sides by -4 we get y = -30.5.

LESSON 5-4 Solve Inequalities Using Addition or Subtraction

Quick Review
When you add or subtract the same number on both sides of an inequality,
the relationship between the sides stays the same.
Solutions to inequalities can be graphed on number lines.

Practice

Question 1.
Carson’s wheelbarrow can hold 345 pounds. If he has 121 pounds
of rock in the wheelbarrow, what number of pounds, p, can he put in
the wheelbarrow without going over the weight limit?
Answer:
The weight that can put in the wheelbarrow is no more than 224 pounds,

Explanation:
Given Carson’s wheelbarrow can hold 345 pounds.
If he has 121 pounds of rock in the wheelbarrow,
So number of pounds p can he put in the wheelbarrow without
going over the weight limit is  121 + p ≤ 345,
121 + p – 121 ≤ 345 – 121, subtracting 121 from both sides we get
p ≤ 224, therefore the weight that can put in the wheelbarrow is
no more than 224 pounds.

Question 2.
Solve x – 19 < 81. Then graph the solution.
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-56
Explanation:
Solving x – 19 < 81 as
x – 19 + 19 < 81 + 19, adding 19 on both sides,
x < 100 and graph of the solution x < 100 is as shown above.

LESSON 5-5 Solve Inequalities Using Multiplication or Division

Quick Review
When you multiply or divide both sides of an inequality by the same positive number,
the inequality remains true. When you multiply or divide both sides of an inequality by
the same negative number, you need to reverse the inequality symbol,
but the inequality remains true.

Practice

Question 1.
Travis has 3 months to save money for a trip. An airplane ticket costs more than $300.
If he saves the same amount of money, a, each month, how much does he need to
save each month to pay for the ticket?
Answer:
Inequality : 3a > 300,
Travis should save more than $100 each month to pay for the ticket,

Explanation:
Given Travis has 3 months to save money for a trip.
An airplane ticket costs more than $300.
If he saves the same amount of money a each month,
So he need to save each month to pay for the ticket is 3a > 300,
Now on simplifying 3a ÷ 3 = 300 ÷ 3, Dividing both sides by 3 we get a >100,
therefore, Travis should save more than $100 each month to pay for the ticket.

Question 2.
Solve –\(\frac{1}{8}\)y ≤ 34. Then graph the solution.
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-57
Explanation:
Solving –\(\frac{1}{8}\)y ≤ 34,
-8 X –\(\frac{1}{8}\)y ≤ -8 X 34, Multiplying both sides by -8 and
reverse the inequality symbol,
y ≥ -272 and graph of the solution y ≥ -272 is as shown above.

LESSON 5-6 Solve Two-Step Inequalities

Quick Review
Inverse relationships and properties can be used to isolate the variable and
solve two step inequalities in the form px + q < r or px + q > r in the same way
that they are used to solve two-step equations.

Practice

Question 1.
The school band gets $5 for each T-shirt they sell at a fundraiser.
They have a goal of raising $150. If $45 has been raised so far,
how many more T-shirts do they have to sell to reach or exceed the goal?
Answer:
The school band needs to sell at least  21 T-shirts,

Explanation:
Given the school band gets $5 for each T-shirt they sell at a fundraiser.
They have a goal of raising $150. If $45 has been raised so far,
more T-shirts they do have to sell to reach or exceed the goal are
45 + 5x ≥ 150,
45 + 5x – 45 ≥ 150 – 45, subtracting 45 from both sides,
5x ≥ 105,
5x ÷ 5 ≥ 105 ÷ 5, dividing both sides by 5 we get x ≥ 21,
therefore the school band needs to sell at least 21 T-shirts.

Question 2.
Solve the inequality –8 –\(\frac{1}{3}\)n ≤ -25.
Answer:
n ≥ 51,

Explanation:
Solving the inequality –8 –\(\frac{1}{3}\)n ≤ -25,
–8 –\(\frac{1}{3}\)n + 8 ≤ -25 + 8, adding 8 on both sides,
–\(\frac{1}{3}\)n ≤ -17,
-3 X –\(\frac{1}{3}\)n ≥ – 3 X -17, Multiplying both sides by -3 and
reverse the inequality symbol we get n ≥ 51.

LESSON 5-7 Solve Multi-Step Inequalities

Quick Review
Solving a multi-step inequality is similar to solving a multi-step equation.
All of the rules and properties for solving one- and
two step inequalities apply to solving multi-step inequalities.

Practice

Question 1.
Solve 1.9(2.3n + 6) + 10.45 > 43.7. Then graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 20.3
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-58

Explanation:
Given to solve 1.9(2.3n + 6) + 10.45 > 43.7,
4.37n + 11.4 + 10.45 > 43.7, using distributive property,
4.37n + 21.85 > 43.7, combining like terms,
4.37n + 21.85 – 21.85 > 43.7 – 21.85, subtracting 21.85 from both sides,
4.37n > 21.85,
4.37n ÷ 4.37 > 21.85 ÷ 4.37, dividing both sides by 4.37 we get
n > 5 and graph of the solution n > 5
 is as shown above.

Question 2.
Solve 4(-2n + 2.5) – 8 ≤ 50. Then graph the solution.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 20.4
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-59
Explanation:
Given to solve 4(-2n + 2.5) – 8 ≤ 50,
-8n + 10 – 8 ≤ 50, using distributive property,
-8n + 2 ≤ 50, combining like terms,
-8n +2 -2 ≤ 50 – 2, subtracting -2 from both sides,
-8n ≤ 48,
-8n ÷ -8 ≥ 48 ÷ -8, dividing both sides by -8 and reverse
the inequality symbol we get n ≥ -6 and
graph of the solution n ≥ -6
 is as shown above.

Topic 5 Fluency Practice

Crisscrossed

Solve each problem. Write your answers in the cross-number puzzle below.
Each digit, decimal point, dollar sign, and percent symbol of your answer goes in its own box.
Round money amounts to the nearest cent as needed.
Envision Math Common Core 7th Grade Answer Key Topic 5 Solve Problems Using Equations and Inequalities 20.5

ACROSS
A. Antonia buys 0.75 yard of fabric at $12.00 per yard.
If she pays 5% sales tax, what is the total cost of the fabric?
B. Five friends plan to split a restaurant bill evenly.
The total cost of the meal is $89.75, and they want to leave a 20% tip.
What amount should each friend pay?
E. Kaylie buys a sweater on sale for $40.11. If the discount is 20% off and
she pays $1.91 in sales tax, what is the original price of the sweater?
F. Randy buys a pair of shoes that were originally priced at $147.
He receives a 35% discount and pays 8.5% sales tax. How much does Randy pay?
G. A basketball player makes 8 of 22 shots in Game 1, 6 of 15 shots in
Game 2, and 10 of 23 shots in Game 3.
What percent of the shots did the player make in the three games?
Answer:
Envision Math Common Core Grade 7 Answer Key Topic 5 Solve Problems Using Equations and Inequalities-60
Across:
A. The total cost of the fabric is $9.45,
B. The amount should each friend pay is $21.54,
E. The original price of the sweater is $47.75,
F. Randy paid $103.67,
G. Percent of the shots did the player make in the three games is 40%,

Explanation:
Across:
A. Given Antonia buys 0.75 yard of fabric at $12.00 per yard.
If she pays 5% sales tax, so 0.75 X $12 = $9,
Now 5% on $9 is 5 X 9 ÷100 = $0.45,
therefore the total cost of the fabric is $9 + $0.45 = $9.45.
B. Given five friends plan to split a restaurant bill evenly.
The total cost of the meal is $89.75 and they want to leave a 20% tip.
So amount should each friend pay must be
89.75 X 20 ÷100 = $17.95 is the  tip,
the total amount is $89.75 + $17.95 = $107.7 which is paid by
5 friends, therefore the amount each friend must pay is
$107.7 ÷ 5 = $21.54.
E. Given Kaylie buys a sweater on sale for $40.11.
If the discount is 20% off and she pays $1.91 in sales tax,
Let x be the original price of the sweater so
Original Price = (Paid Price – Tax) + 20% discount,
x = (40.11 -1.91) + 20% discount,
x  = $38.20 +( (20 X x) ÷ 100),
x – (20x ÷ 100)= $38.20,
100x – 20x = $38.20 X 100,
80x = $3,820.
x  = $3,820 ÷ 80,
x = $47.75.
F. Given Randy buys a pair of shoes that were originally priced at $147.
He receives a 35% discount and pays 8.5% sales tax.
Let Randy paid p,
Randy receives 35% discount means
($147 – ($147 X 35% discount)) = ($147 – $51.45) =  $95.55,
on $95.55 Randy pays 8.5% sales tax so 95.55 X 8.5 ÷ 100 = $8.12175,
Therefore Randy paid p = $95.55 + $8.12175 = $103.67175 ≈ $103.67.
G. Given a basketball player makes 8 of 22 shots in Game 1,
6 of 15 shots in Game 2 and 10 of 23 shots in Game 3,
In Game 1 percent of the shots did the player make is 8 ÷ 22 = 0.36 = 36%,
In Game 2 percent of the shots did the player make is 6 ÷ 15 = 0.40 = 40%,
In Game 3 percent of the shots did the player make is 10 ÷ 23 = 0.43 = 43%,
Therefore percent of the shots did the player make in the three games is
(36% + 40% + 43%) ÷ 3 = 39.33% ≈ 40%.

DOWN
A. Jack buys a tablet that costs $99 and a memory card that costs $15.
He has a coupon for a 15% discount. What is the amount of the discount on the two items?
B. Tara buys two pairs of socks for $4.99 each and three T-shirts for $11.45 each.
If she pays 6% sales tax, what is the total amount of her purchase?
C. Sunil receives a 20% discount on a concert ticket that costs $75.
If Sunil pays $3.30 in sales tax on the discounted ticket, what is the sales tax rate?
D. Dylan works for 4 hours and is paid $17.50 per hour. He must pay 15% in income taxes.
What amount does he earn after taxes?
E. Miles earns a 6% commission on each vehicle he sells.
Today he sold a truck for $18,500 and a car for $9,600.
What is the total amount of his commission for these vehicles?
Answer:
A. The amount of the discount on the two items is $17.10,
B. The total amount of Tara’s purchase is $47.00,
C. The sales tax rate is 5.5%,
D. Dylan earn after taxes is $59.50,
E. The total amount of Miles commission for these vehicles is $1,686,

Explanation:
A. Given Jack buys a tablet that costs $99 and a memory card that costs $15.
He has a coupon for a 15% discount. So tablet costs $99 – ($99 X 15 ÷ 100) =
$99 –  $14.85 = $84.15 and Memory card costs $15 – ($15 X 15 ÷ 100) =
$15 – $2.25 = $12. 75, Therefore the amount of the discount on the two items is
discount amount on tablet + discount amount on memory card = $ 14.85 +  $ 2.25 = $17.10.
B. Given Tara buys two pairs of socks for $4.99 each and three T-shirts for $11.45 each.
If she pays 6% sales tax, To find the total amount of her purchase first we will calculate
cost for socks + cost for T-shirts and then add sales tax too, so
2($4.99) + 3(11.45) = $9.98 + $34.35 = $44.33,
Now sales tax = $44.33 X 6 ÷ 100 = $2.6598, therefore $44.33 + $2.6598 = $46.9898 ≈ $47.00.
C. Given Sunil receives a 20% discount on a concert ticket that costs $75.
If Sunil pays $3.30 in sales tax on the discounted ticket,
The discounted ticket price is ($75 – $75 X 20 ÷ 100) = $75 – $15 = $60,
let the sales rate tax is r, so $3.30 = r% of 60, therefore r = (3.30 ÷ 60) X 100= 0.55 X 100 = 5.5%.
D. Given Dylan works for 4 hours and is paid $17.50 per hour.
He must pay 15% in income taxes. So amount does he earn after taxes would be
first he gets $17.50 X 4 = $70, So amount paid to income tax will be  $70 X 15 ÷ 100 = $10.5,
Therefore Dylan earn after taxes is $70 – $10.5 = $59.50.
E. Given Miles earns a 6% commission on each vehicle he sells.
Today he sold a truck for $18,500 and a car for $9,600.
So first commission on truck sold is $18,500 X 6 ÷ 100 = $1,110 and
commission on car sold is $9,600 X 6 ÷ 100 = $576,
therefore the total amount of his commission for these vehicles is
$1,110 + $576 = $1,686.