Category: Envision Math

Envision Math 4th Grade Textbook Answer Key Topic 2.3 Using Mental Math to Add and Subtract

Using Mental Math to Add and Subtract

How can you use mental math to add and subtract?
Properties can sometimes help you add using mental math. How many years have Ms. Walston and Mr. Randall been teaching? What is the total number of years all of the teachers in the chart have been teaching?

Other Examples

Add using mental math.

Find 135 + 48.

Use breaking apart to find a ten.
Adding 5 to 135 is easy. Break apart 48.

135 + 5 = 140
140 + 43 = 183
So, 135 + 48 = 183.

Use compensation.
135 + 48
135 + 50 = 185
Think I added 2 too many,
so I will subtract 2.
185 – 2 = 183
So, 135 + 48 = 183.

Subtract using mental math.
Find 400 – 165.
Use counting on.

165 + 5 = 170
170 + 30 = 200
200 + 200 = 400
5 + 30 + 200 = 235
So, 400 -165 = 235.
Use compensation.

Find 260 – 17.
It is easy to subtract 20.
260 – 20 = 240
Think I subtracted 3 too many,
so I will add 3.
240 + 3 = 243
So, 260 – 17 = 243.

Commutative Property of Addition
You can add two numbers in any order.

Ms. Walston and Mr. Randall have been teaching a combined total of 42 years.

Associative Property of Addition

You can change the grouping of addends.

The total number of years the three teachers have been teaching is 47 years.

Identity Property of Addition

Adding zero does not change the number.
12 + 0 = 12

Guided Practice*

Do You Know how?

In 1 through 6, use mental math to add or subtract.

Question 1.
86 + 25
Answer:

Question 2.
497 + 0
Answer:

Question 3.
566 – 359
Answer:

Question 4.
169 – 48
Answer:

Question 5.
239 + 509
Answer:

Question 6.
(40 + 5) + 8
Answer:

Do You Understand?

Question 7.
How could you use compensation to find 391 – 26?
Answer:

Question 8.
Writing to Explain Explain how you used mental math to find the answer to Exercise 4.

Independent Practice

Leveled Practice In 9 through 18, use mental math to complete the calculation.

Question 9.
400 – 227

Answer:

Question 10.
500 – 89

Answer:

Question 11.
906 – 289

Answer:

Question 12.
7,000 + 2,130

Answer:

Question 13.
583 + 317

Answer:

Question 14.
125 + 28

Answer:

Question 15.
1,700 – 315
Answer:

Question 16.
2,000 + 4,996
Answer:

Question 17.
438 – 129
Answer:

Question 18.
0 + 284
Answer:

Problem Solving

For 19 through 21 , use the table to the right.

Question 19.
Which state has the greatest land area in square miles?
Answer:

Question 20.
Which two states shown in the table have the smallest difference in land area?
Answer:

Question 21.
Which two states shown in the table have the greatest difference in land area?
Answer:

Question 22.
Colin had 148 CDs in his collection. He traded 32 of them for 23 that he really wanted. How many CDs does Colin now have in his collection? Use mental math.
A. 106 CDs
B. 108 CDs
C. 116 CDs
D. 139 CDs
Answer:

Question 23.
Ms. Gomez’s class collected pencils for the community school supplies drive. Ethan’s group brought in 143 pencils and Marcelina’s group added 78 more. How many pencils did the groups contribute altogether?
A. 184 pencils
B. 204 pencils
C. 221 pencils
D. 245 pencils
Answer:

Question 24.
Number Sense Is 881 – 262 more or less than 500? Explain how you can tell using mental math.
Answer:

Question 25.
Writing to Explain How can you use mental math to subtract 158 – 29?
Answer:

Question 26.
An adult human body has a total of 206 bones. There are 300 bones in a child’s body because some of a child’s bones fuse together as a child grows. How many more bones are in a child’s body than in an adult’s body?


Answer:

Question 27.
Number Sense Write two numbers that have a 6 in the ones place and an 8 in the hundreds place.
Answer:

Algebra Connections

Solving Number Sentences with Addition and Subtraction

A number sentence uses the equal sign (=) to show that two expressions have the same value. Fill in the box in each number sentence with the whole number that makes the number sentence true. Check your answers.

Example:

Think What number plus 8 equals 35?
When solving an addition number sentence, use subtraction to identify the missing number.
Think What is 35 minus 8?
Subtract 8 from 35.
35 – 8 = 27
Now, add 8 and 27.
8 + 27 = 35

Copy and complete each number sentence.

Question 1.
7 + = 31
Answer:

Question 2.
+ 6 = 21
Answer:

Question 3.
26 – = 25
Answer:

Question 4.
56 – = 38
Answer:

Question 5.
– 47 = 12
Answer:

Question 6.
66 + = 85
Answer:

Question 7.
– 98 = 1
Answer:

Question 8.
103 – = 72
Answer:

Question 9.
10 + = 13
Answer:

Question 10.
– 8 = 12
Answer:

Question 11.
1 + = 7
Answer:

Question 12.
744 – = 327
Answer:

For 13 through 16, copy and complete the number sentence below each problem. Use it to help explain your answer.

Question 13.
Cheryl made 8 free-throw shots. She shot a total of 10 free-throw shots. How many free-throw shots did she miss?
8 + = 10

Question 14.
7 rabbits less than a certain number of rabbits is 13 rabbits. What is the value of the variable?
– 7 = 13
Answer:

Question 15.
George delivered 118 newspapers in two days. He delivered 57 newspapers the first day. How many newspapers did George deliver the second day?
57 + = 118
Answer:

Question 16.
The cost of an apple is 39¢. Robert had 25¢ in his pocket. How much more money did Robert need to purchase the apple?
25 + = 39
Answer:

Envision Math 4th Grade Textbook Answer Key Topic 1 Reteaching

Set A, pages 4-6,8-9

Use a place-value chart to write the expanded Remember that periods can help form and word form of 26,500.

Expanded form: 20,000 + 6,000 + 500

Word form: twenty-six thousand, five hundred

Remember that periods can help you read large numbers. Use place-value charts to write each number in expanded form and word form.

Question 1.
7,549
Answer:

Question 2.
27,961
Answer:

Question 3.
321,209
Answer:

Question 4.
3,454
Answer:

Question 5.
6,792,365
Answer:

Question 6.
15,164,612
Answer:

Question 7.
413,109,657
Answer:

Question 8.
83,251
Answer:

Question 9.
4,806
Answer:

Question 10.
6,138,405
Answer:

Set B, pages 10–13

Write > or < for each .

45,423 44,897

Step 1
Use place value to compare.

Step 2
Start comparing from the left.

Step 3
Look for the first digit that is different.
45,423
44,897
5 > 4
So, 45,423 > 44,897.

Remember that a number line can be used to compare numbers. Write > or < for each .

Question 1.
11,961 12,961
Answer:

Question 2.
23,901 23,899
Answer:

Question 3.
42,661,907 42,659,824
Answer:

Question 4.
735,291,000 735,291,001
Answer:

Question 5.
6,103,582 6,130,449
Answer:

Question 6.
462,918 461,349
Answer:

Question 7.
8,457 8,451
Answer:

Question 8.
163,492,708 163,492,807
Answer:

Question 9.
38,605 38,650
Answer:

Question 10.
871,943 871,934
Answer:

Set C, pages 14-15

Use expanded form to compare and order numbers. Which is greater, 3,500 or 3,005? 3,500 = 3,000 + 500 3,005 = 3,000 + 5 500 > 5
So, 3,500 > 3,005.
Write the numbers from greatest to least.
3,050       3,005         3,500
Write the numbers in expanded form.
3,050 = 3,000 + 50
3,005 = 3,000 + 5
3,500 = 3,000 + 500
500 > 50 > 5
So, 3,500 > 3,050 > 3,005.

Remember to use a place-value chart to help compare and order numbers.
Write each number in expanded form. Then, copy and complete by writing > or < for each .

Question 1.
8,500 8,005
Answer:

Question 2.
2,002 2,020
Answer:

Question 3.
3,600 3,006
Answer:

Question 4.
7,004 7,040
Answer:

Order the numbers from greatest to least.

Question 5.
1,009 1,900 1,090
Answer:

Question 6.
6,008 6,800 6,080
Answer:

Set D, pages 16-17

Using only hundreds and tens blocks, how many ways can you make 440?

Record the combinations using an organized list.

Remember that the way you organize a list can help you find all the possibilities in a problem.
Solve. Make an organized list to help you.

Question 1.
A game has yellow, red, black, and green counters. How many 2-color combinations can you make?
Answer:

Question 2.
Troy collects plastic banks. He has three different plastic banks: a pig, a cow, and a frog. How many ways can he arrange his banks on a shelf?
Answer:

Envision Math 4th Grade Textbook Answer Key Topic 1.5 Problem Solving

Problem Solving

Make an Organized List

Arthur is tiling a bathroom wall. He has 520 wall tiles. He wants to arrange them in patterns of hundreds and tens. Using only hundreds and tens blocks, how many ways can he make 520?

Guided Practice*

Do you know HOW?

Solve. Make an organized list to help you.

Question 1.
It costs Celia 50¢ admission to enter the aquarium. How many different ways can Celia pay the admission using only quarters, dimes, and nickels?
Answer:

Do you UNDERSTAND?

Question 2.
What were the titles for the columns of your list in Problem 1?
Answer:

Question 3.
Write a Problem Write a problem that you can solve using an organized list.
Answer:

Independent Practice

Solve.

Question 4.
Using only hundreds blocks and tens blocks, list the ways to show 340.
Answer:

Question 5.
Simon asked Margaret to guess a number. He gave these hints.

• The number has 3 digits.
• The digit in the 100s place is less than 2.
• The digit in the 10s place is greater than 8.
• The number is even.

What are the possible numbers?

Question 6.
Make a list showing the ways you can make a dollar using only quarters, dimes, and nickels using no more than one nickel and no more than 9 dimes.

Read & Understand Plan

Plan
Record the combinations using an organized list.

There are 6 ways to make 520.

Question 7.
Lou’s sandwiches are made with either wheat or white bread and have only one type of cheese—
Swiss, Cheddar, American, or Mozzarella. How many different kinds of sandwiches can Lou make?
Answer:

Question 8.
A magazine has a total of 24 articles and ads. There are 9 articles. How many ads are there?

Answer:

Question 9.
Janie is making a bracelet. She has 1 red bead, 1 blue bead, and 1 white bead. How many possible ways can Janie arrange the beads?
Answer:

Question 10.
Reasoning What two numbers have a sum of 12 and a difference of 4?
Answer:

Question 11.
Alan has a cat, a goldfish, and a dog. He feeds them in a different order each day. How many different ways can he feed his pets?
Answer:

Question 12.
Heather is writing a 3-digit number. She uses the digits 1, 5, and 9. What are the possible numbers she can write?
Answer:

Question 13.
At the driving range, James wants to buy 200 golf balls. The golf balls are sold in buckets of 100, 50, and 10 golf balls. How many different ways can James buy 200 golf balls?

Answer:

Envision Math 4th Grade Textbook Answer Key Topic 1.4 Understanding Zeros in Place Value

Understanding Zeros in Place Value

How do you compare and order numbers with zeros?

Lena wrote three book reports. Which report used the most disk space on her computer? Use expanded form to compare and order numbers.

Guided Practice*

Do you know HOW?

In 1 and 2, write each number in expanded form. Then write > or < for each .

Question 1.
6,400 6,004
Answer:

Question 2.
1,002 1,020
Answer:

In 3 and 4, order the numbers from greatest to least.

Question 3.
7,002 7,200 7,020
Answer:

Question 4.
8,006 8,600 8,060
Answer:

Do You Understand?

Question 5.
Number Sense Write a 5-digit number with 0 in the hundreds place and 0 in the ones place. Then, write your number in expanded form.
Answer:

Question 6.
Looking at the chart above, which book report used the least amount of disk space on Lena’s computer? How much disk space did it use?

Independent Practice

Leveled Practice In 7 through 17, compare. Write < or > for each .

Question 7.
1,040 1,000 + 40
1,004 = 1,000 + 4
1,040 1,004
Answer:

Question 8.
18,020 = 10,000 + 8,000 + 20
18,200 = 10,000 + 8,000 + 200
18,020 18,200
Answer:

Question 9.
2,070 2,700
Answer:

Question 10.
13,200 13,020
Answer:

Question 11.
5,406 5,460
Answer:

Question 12.
4,130 4,103
Answer:

Question 13.
31,002 30,102
Answer:

Question 14.
26,008 26,800
Answer:

Question 15.
10,250 10,205
Answer:

Question 16.
60,802 68,002
Answer:

Question 17.
42,910 42,901
Answer:

Compare the first two numbers. Which is greater, 9,050 or 9,005?
9,050 = 9,000 + 50
9,005 = 9,000 + 5
50 > 5
So, 9,050 > 9,005.

Write the numbers from greatest to least.
9,050 9,005 9,500
Write the numbers in expanded form.
9,050 = 9,000 + 50
9,005 = 9,000 + 5
9,500 = 9,000 + 500
500 > 50 > 5
So, 9,500 > 9,050 > 9,005.
Grandfather’s Journey took up the most disk space on Lena’s computer.

In 18 through 21 , order the numbers from greatest to least.

Question 18.
3,007 3,070 3,700
Answer:

Question 19.
9,800 9,008 9,080
Answer:

Question 20.
30,200 30,002 32,000 30,020
Answer:

Question 21.
40,060 40,006 40,600 46,000
Answer:

For 22 and 23, pick four numbers between 143,000 and 144,000. Include exactly two zeros in each number.

Question 22.
Order the numbers you chose from least to greatest.
Answer:

Question 23.
What do the numbers have in common?
Answer:

For 24 and 25, use the chart at the right.

Question 24.
Which month were the most carnival tickets sold?
Answer:

Question 25.
Writing to Explain Explain why this statement is NOT correct: More tickets were sold in June than August because 40 > 20.
Answer:

Question 26.
The chart at the right shows the results of this year’s reading contest. Which could NOT be the missing number?

A. 32,006
B. 33,006
C. 33,060
D. 34,006
Answer:

Envision Math 4th Grade Textbook Answer Key Topic 1.2 Millions

Millions

What are some ways to represent numbers in the millions?

From 2001 through 2005, 356,039,763 fans attended professional baseball games. Write the expanded form and word form for 356,039,763.
Use a place-value chart to help.

Guided Practice*

Do you know HOW?

In 1 and 2, write the number in word form. Then, tell the value of the red digit in each number.

Question 1.
75,600,295
Answer:

Question 2.
249,104,330
Answer:

In 3 through 6, write the number in expanded form.

Question 3.
6,173,253
Answer:

Question 4.
75,001,432
Answer:

Question 5.
16,107,320
Answer:

Question 6.
430,290,100
Answer:

Question 7.
What is the value of 5 in 356,039,763?
Answer:

Question 8.
What is the value of 9 in 356,039,763?
Answer:

Question 9.
Between 1996 and 2000
335,365,504 fans attended games. Which digit is in the millions place in 335,365,504?
Answer:

Independent Practice

In 10 through 12, write each number in standard form.

Question 10.
300,000,000 + 40,000,000 + 7,000,000 + 300,000 + 10,000 + 6,000 + 20 + 9
Answer:

Question 11.
900,000,000 + 20,000,000 + 6,000,000 + 20,000 + 4,000 + 10
Answer:

Question 12.
80,000,000 + 1,000,000 + 600,000 + 20,000 + 900 + 40 + 8
Answer:

In 13 through 16, write the number in word form. Then, tell the value of the red digit in each number.

Question 13.
7,915,878
Answer:

Question 14.
23,341,552
Answer:

Question 15.
21 4,278,216

Question 16.
334,290,652
Answer:

Use a place-value chart to show 356,039,763.

There is a 3 in the hundred millions place. Its value is 300,000,000.

In 17 through 20, write the number in expanded form. Then, tell the value of the red digit in each number.

Question 17.
7,330,968
Answer:

Question 18.
30,290,447
Answer:

Question 19.
1 33,958,840
Answer:

Question 20.
309,603,114
Answer:

Problem Solving

Question 21.
Writing to Explain Which number will take less time to write in expanded form, 800,000,000 or 267,423?

Question 22.
Write the expanded form of 123,456,789 and 987,654,321. Which digit has the same value in both numbers?
Answer:

Question 23.
In 2005, seventy-four million, nine hundred fifteen thousand, two hundred sixty-eight fans attended baseball games. Which choice shows this number in standard form?
A. 74,015,268
B. 74,900,268
C. 74,905,268
D. 74,915,268
Answer:

Question 24.
Write the standard form of a 9-digit number with a 5 in the millions place and a 9 in the tens place.
a. Write a number that is ten million more than the number you chose.
b Write a number that is one million less than the number you chose.
Answer:

Question 25.
Number Sense Fort Knox holds 147,300,000 ounces of gold. Write the number that is one million more

Answer:

Envision Math 4th Grade Textbook Answer Key Topic 1.1 Thousands

Review What You Know

Question 1.
“Baby,” the snake, weighs 403 pounds. Is it the heaviest snake that is living in captivity? You will find out in Lesson 1-3.

Answer:

Question 2.
How many towns and cities were there in California in 2004? You will find out in Lesson 1-1.

Answer:

Review What You Know!

Vocabulary

Choose the best term from the box

Question 1.
A group of three digits in a number separated by a comma is a __.
Answer:

Question 2.
A __ is a line that shows numbers in order using a scale.
Answer:

Question 3.
The number 8 is an ? number.
Answer:

Question 4.
The number 5 is an __ number.
Answer:

Comparing Numbers
Compare. Use >, <, or = for each .

Question 5.
13 10
Answer:

Question 6.
7 7
Answer:

Question 7.
28 29
Answer:

Question 8.
14 5
Answer:

Question 9.
43 34
Answer:

Question 10.
0 1
Answer:

Question 11.
52 52
Answer:

Question 12.
13 65

Question 13.
22 33

Place Value

Tell if the underlined digit is in the ones, tens, or hundreds place.

Question 14.
346
Answer:

Question 15.
17
Answer:

Question 16.
921
Answer:

Question 17.
106
Answer:

Question 18.
33
Answer:

Question 19.
47
Answer:

Question 20.
217
Answer:

Question 21.
320

Question 22.
810
Answer:

Question 23.
1,006
Answer:

Question 24.
999
Answer:

Question 25.
1,405
Answer:

Question 26.
Writing to Explain How does using commas to separate periods help you read large numbers?

Thousands

What are some ways to represent numbers in the thousands?
An altimeter measures height above sea level. Jill’s altimeter shows she is 3,241 feet above sea level. There are different ways to represent 3,241.

Another Example

How do you read and write numbers in the thousands?

Another bicycle racer’s altimeter shows he is 5,260 feet above sea level. Write 5,260 in standard form, expanded form, and word form.
When writing a number in standard form,

write only the digits: 5,260.

Each group of 3 digits starting from the right forms a period.
A number in expanded form is written as the sum of the value of the digits: 5,000 + 200 + 60 + 0.
Use periods in the place-value chart to write
5,260 in word form: five thousand, two hundred sixty.

Explain It

Question 1.
Explain why the value of 5 in 5,264 is 5,000.
Answer:

Question 2.
Is the expanded form for 5,260 the same as for 5,206?
Answer:

You can represent numbers using place-value blocks.

You can represent numbers on a number line.

Guided Practice*

Do you know HOW?

In 1 through 4, write the word form, and tell the value of the red digit in each number.

Question 1.
15,324
Answer:

Question 2.
1 35,467
Answer:

Question 3.
921,382
Answer:

Question 4.
275,206
Answer:

In 5 and 6, write the expanded form.

Question 5.
42,158
Answer:

Question 6.
63,308
Answer:

Do you UNDERSTAND?

Question 7.
If Jill climbed 100 feet more, what would her altimeter read?
Answer:

Question 8.
What is the value of the 2 in 3,261? the 3? the 1?
Answer:

Question 9.
Write one hundred one thousand, eleven in standard form.
Answer:

Independent Practice

Leveled Practice In 10 through 13, write each number in standard form

Question 10.

Answer;

Question 11.

Answer:

Question 12.

Answer:

Question 13.

Answer:

Independent Practice

In 14 and 15, write each number in standard form.

Question 14.
Eighty-three thousand, nine hundred two
Answer:

Question 15.
Three hundred twenty-one thousand, two hundred nine
Answer:

In 16 and 17, write each number in expanded form.

Question 16.
Four hundred ninety-seven thousand, three hundred thirty-two
Answer:

Question 17.
Twenty-one thousand, eight hundred seven
Answer:

In 18 and 19, write each number in word form.

Question 18.
300,000 + 8,000 + 20 + 9
Answer:

Question 19.

Problem Solving

Question 20.
Reasoning The pedometer below counts the number of steps you walk. It can show 5 digits. What is the greatest number it can show?

Answer:

Question 21.
A town library has 124,763 books and 3,142 DVDs. This year, they bought 1,000 books and 2,000 DVDs. How many books does the library have now?
A. 5,142 books
B. 23,142 books
C. 125,763 books
D. 134,763 books
Answer:

Question 22.
Number Sense Which digit is in the same place in all three numbers below? Name the place-value position.
574,632 24,376 204,581

Question 23.
Reasoning What is the greatest 4-digit number you can write? What is the least 4-digit number?
Answer:

Question 24.
In 2004, California had 1,080 towns and cities. Use place-value blocks to represent 1,080. If this number increases by 300 in ten years, how many towns and cities will there be in ten years?
Answer:

Mixed Problem Solving

Question 1.
How many more Kemp Ridley’s Sea Turtles were there in 1947 than in 1968?
Answer:

Question 2.
Did the population of Kemp Ridley’s Sea Turtles increase or decrease between 1991 and 2000?
Answer:

Question 3.
How many fewer Kemp Ridley’s Sea Turtles were found nesting in 1991 than in 1968?
Answer:

Question 4.
Which is taller: the California jewel-flower or the Calistoga popcorn flower?
Answer:

Question 5.
Which is shorter: the Calistoga popcorn flower or the Slenderhorned spineflower?
Answer:

Question 6.
Order the California jewel-flower, the Sacramento Orcutt grass, and the Slender-horned spineflower from tallest to shortest using
their heights.

For 7 and 8, use the information below.

Question 7.
Which digit in the number 155,959 is in the thousands place? What does the 1 mean in this number?
Answer:

Question 8.
Strategy Focus Solve the problem using the strategy Write an Equation. How many square miles of California’s total area is covered by water?
Answer:

Envision Math 2nd Grade Textbook Answer Key Topic 2 Reteaching

Set A

You can change the order of the addends. The sum will stay the same.

Write the sum. Then change the order of the addends and complete the problem.

Question 1.
9 + 3 = __
__ + __ = ___

Question 2.
6 + 4 = __
__ + __ = ___
Answer:

Set B

You can add any two numbers first.

I can add 6 and 4 first. 6 + 4 = 10. Then I can add the 3.10 + 3 = 13

Circle the numbers you add first. Write their sum in the box to the right. Then complete the problem

Question 3.

Answer:

Question 4.

Answer:

Set C

You can use a doubles fact to help you add a near double.

4 + 4 = 8
3 + 4 is 1 less than 4 + 4.
So, 3 + 4 = 7.

Complete the doubles facts. Use the doubles facts to solve the near doubles.

Question 5.

Answer:

Question 6.

Answer:

Set D

You can make 10 to help you add 8

Make 10 to add 8.

Question 7.
8 + 4 = ?

Answer:

Question 8.
5 + 8 = ?

Answer:

Envision Math 2nd Grade Textbook Answer Key Topic 2.8 Problem Solving

Problem Solving
Draw a Picture and Write Draw a Picture and Write a Number Sentence

Question 1.
__ + __ = ___
Answer:

Question 2.
__ + __ = __
Answer:

Question 3.
__ + __ = __
Answer:

Home Connection Your child drew pictures and wrote number sentences to solve math story problems.
Home Activity Place up to 10 small items in 3 piles and ask your child how many there are in all. He or she should place the items on the mat on this page and write a number sentence on a separate sheet of paper
to solve the problem. Repeat with different numbers of items.
AF 1.3 Solve addition and subtraction problems by using data from simple charts, picture graphs, and number sentences. Also AF 1.2, MR 1.2, MR 2.1.

Guided Practice

Use the table above. Draw counters and write number sentences to solve.

Question 1.
How many points did Benita score in all?

Answer:

Question 2.
How many points did Billy score altogether?

__ + __ + __ = __ points
Answer:

Do you understand? Sam scored 12 points in all. Write a number sentence for Sam’s points.

__ + __ + __ = 12 points

Independent Practice

Tomaz and Amy planted flowers. The table shows how many flowers they planted. Draw counters and write number sentences to solve.

Answer:

Question 3.
How many flowers did Tomaz plant in all?

__ + __ + __ = __ flowers
Answer:

Question 4.
How many flowers did Amy plant altogether?

__ + __ + ___ = __ flowers
Answer:

Problem Solving

Solve the problems below.

Question 5.
Kathy and Julio collect shells. The table shows how many shells each collected. How many shells did Julio collect altogether? Draw counters and write number sentences to solve.

Answer:

Question 6.
Which number sentence tells how many shells Kathy had collected after Weeks 1 and 2?

Answer:

Question 7.
Journal Explain what addition strategy you used to check your answer to exercise 5.

Answer:

Envision Math 2nd Grade Textbook Answer Key Topic 2.6 Making 10 to Add 9

Making 10 to Add 9

Question 1.

Answer:

Question 2.

Answer:

Question 3.

Answer:

Question 4.

Answer:

Home Connection Your child explored strategies for making 10 to help add with 9.
Home Activity Have your child use pennies to make a group of 9 and a group of 5. Ask your child to show you how to make a group of 10 pennies to help find the sum.
AF 1.1, Grade 1 Write and solve number sentences from problem situations that express relationships
involving addition and subtraction. Also AF 1.0.

Guided Practice

Make 10 to add 9.
Use counters and your workmat.

Question 1.

Answer:

Question 2.

Answer:

Do you understand? Compare adding 9 to any number and adding 10 to that same number. What is different?

Independent Practice

Make 10 to add 9.
Use counters and your workmat.

Question 3.

Answer:

Question 4.

Answer:

Question 5.

Answer:

Question 6.

Answer:

Question 7.
8 +9 = ___
Answer:

Question 8.
9 + 7 = ___
Answer:

Question 9.
9 +2 = ___
Answer:

Question 10.
9 +9 =___
Answer:

Question 11.
1 +9 = ___
Answer:

Question 12.
5 + 9 = ___
Answer:

Number Sense
Find the missing number.

Question 13.
9 + 3 = + 2
Answer:

Question 14.
+ 9 = 10 + 6
Answer:

Problem Solving

Solve the problems below.

Question 15.
Tan’s team has 9 points. They score 7 more points. How many points do they have in all?
___ points
Answer:

Question 16.
Ana’s team has 9 bats. Nico’s team has 8 bats. How many bats are there in all?
___ bats
Answer:

Question 17.
Mary wrote an addition sentence. What number makes her addition sentence true? Mark your answer.

Answer:

Question 18.
Journal Draw a picture to show how you can make 10 to help you add 5 + 9.

Answer:

Envision Math 2nd Grade Textbook Answer Key Topic 2.5 Adding Three Numbers

Adding Three Numbers

Question 1.
My numbers: ____ , ____ , ____

Answer:

Question 2.
My numbers: ____ , ____ , ____

Answer:

Question 3.
My numbers: ____ , ____ , ____

Answer:

Question 4.
My numbers: ____ , ____ , ____

Answer:

Home Connection Your child added three numbers.
Home Activity Have your child use pennies or other small objects to show different ways to add 9 + 1 + 4.
Continue by adding three other numbers less than 10.
AF 1.1 Use the commutative and associative rules to simplify mental calculations and to check results.
Also MR 1.0, MR 1.1, MR 2.0.

Guided Practice

Find each sum in two different ways.
Circle the numbers you added first.
Then write their sum in the box.

Question 1.

Answer:

Question 2.

Answer:

Question 3.

Answer:

Question 4.

Answer:

Do you understand? What are two different ways you could add 3 + 4 + 7? Explain.

Independent Practice

Write the sum.
Circle the numbers you added first

Question 5.
3 + 8 + 2 =
Answer:

Question 6.
5 + 7 + 5 =
Answer:

Question 7.
9 + 4 + 1 =
Answer:

Question 8.
6 + 5 + 7 = ___
Answer:

Question 9.

Answer:

Question 10.

Answer:

Question 11.

Answer:

Question 12.

Answer:

Algebra
Find the missing number

Question 13.
6 + + 3 = 10
Answer:

Question 14.
5 + 5 + = 15
Answer:

Problem Solving

Solve the problems below.

Question 15.
There are three kinds of balls. List 3 different ways you can add to find the total number of balls.

_________________
_________________
_________________
Answer:

Question 16.
Josie has 2 baseballs and her brother has 4.
They then got 8 more as a gift.

How many baseballs do they now have in all?

Answer:

Question 17.
Journal Use pictures, numbers, or words to show two different ways to add 4 + 2 + 6. Explain your thinking

Answer: