{"id":7800,"date":"2023-12-19T12:05:57","date_gmt":"2023-12-19T06:35:57","guid":{"rendered":"https:\/\/envisionmathanswerkey.com\/?p=7800"},"modified":"2023-12-20T10:49:16","modified_gmt":"2023-12-20T05:19:16","slug":"envision-math-common-core-grade-3-answer-key-topic-8","status":"publish","type":"post","link":"https:\/\/envisionmathanswerkey.com\/envision-math-common-core-grade-3-answer-key-topic-8\/","title":{"rendered":"enVision Math Common Core Grade 3 Answer Key Topic 8 Use Strategies and Properties to Add and Subtract"},"content":{"rendered":"

Go through the\u00a0enVision Math Common Core Grade 3 Answer Key<\/a>\u00a0Topic 8 Use Strategies and Properties to Add and Subtract<\/strong>\u00a0regularly and improve your accuracy in solving questions.<\/p>\n

enVision Math Common Core 2nd Grade Answers Key Topic 8 Use Strategies and Properties to Add and Subtract<\/h2>\n

Essential Question:<\/strong> How can sums and differences be estimated and found mentally?
\n\"Envision
\nEnVision STEM Project: Traits and the Environment<\/strong>
\nDo Research<\/strong> Use the Internet or other sources to find out how the environment can influence plants or animals. Describe a trait in an animal or plant that can change due to the environment.
\nJournal: Write a Report<\/strong> Include what you found. Also in your report:<\/p>\n

    \n
  • Make a table that includes the plant or animal, the trait, and changes in the environment. Record any related data about the environment, such as temperature or rainfall.<\/li>\n
  • Include information about why the trait is useful.<\/li>\n
  • Write and solve addition problems using your data. Use estimation to check for reasonableness.<\/li>\n<\/ul>\n

    Review What You Know<\/strong><\/p>\n

    Vocabulary<\/strong>
    \nChoose the best term from the box. Write it on the blank.<\/p>\n

    \u2022 difference
    \n\u2022 equation
    \n\u2022 number line
    \n\u2022 sum<\/p>\n

    Question 1.
    \nThe amount that is left after you subtract is the ___.
    \nAnswer: The amount that is left after you subtract is the difference.<\/p>\n

    Question 2.
    \nA line that shows numbers in order from left to right is a(n) ___.
    \nAnswer:\u00a0 A line that shows numbers in order from left to right is a number line<\/p>\n

    Question 3.
    \nThe total when you add is the ___.
    \nAnswer: The total when you add is the sum.<\/p>\n

    \"Math<\/p>\n

    Question 4.
    \nBoth sides of a(n) ___ are equal.
    \nAnswer: Both sides of an equation are equal.<\/p>\n

    Addition and Subtraction Strategies
    \nFind the sum or difference. Show your work.<\/p>\n

    Question 5.
    \n32 + 58
    \nAnswer:
    \n32 + 58
    \n(30 + 2) + (50 +8) = 90<\/p>\n

    Question 6.
    \n27 + 46
    \nAnswer:
    \n27 + 46 = 73
    \n(20 + 7) + (40 + 6) = 73<\/p>\n

    Question 7.
    \n73 – 52
    \nAnswer:
    \n73 – 52 = 21
    \n(70 + 3) – ( 50 + 2) = 21<\/p>\n

    Question 8.
    \n63 +16
    \nAnswer:
    \n63 + 16 = 79
    \n(60 + 3) + (10 + 6) = 79<\/p>\n

    Question 9.
    \n88 – 28
    \nAnswer:
    \n88 – 28 = 60
    \n(80 + 8) – (20 + 8) = 60<\/p>\n

    Question 10.
    \n76 – 49
    \nAnswer:
    \n76 – 49 = 27
    \n(70 + 6) – (40 + 9) = 27<\/p>\n

    Numerical Expressions<\/strong><\/p>\n

    Question 11.
    \nAtif puts 45 rocks in a display box. He has 54 rocks in all. Which expression can be used to find how many rocks are not in the display box?
    \nA. 45 + 54
    \nB. 45 + 45
    \nC. 54 – 45
    \nD. 54 \u2013 54
    \nAnswer:
    \nOption C is the correct answer because
    \nTotal rocks = 54
    \nAtif puts in a display box = 45
    \nThen total rocks – Atif puts in a display box = rocks are not in a display box.<\/p>\n

    Counting Money no<\/strong><\/p>\n

    Question 12.
    \nTony has the coins shown at the right. Does he have enough money to buy a toy car that costs 86\u00a2? Explain.
    \n\"Envision
    \nAnswer:
    \nNo, because the sum of all cents is not enough to buy a toy car.<\/p>\n

    Pick a Project<\/strong><\/p>\n

    PROJECT 8A<\/strong>
    \nHow much citrus is grown in Florida?
    \nProject: Plan a Citrus Grove
    \n\"Envision<\/p>\n

    PROJECT 8B<\/strong>
    \nWould you like to travel across the country?
    \nProject: Create and Perform Skits
    \n\"Envision<\/p>\n

    PROJECT 8C<\/strong>
    \nHow can you add and subtract large numbers without a calculator?
    \nProject: Make a Mental Math Game
    \n\"Envision<\/p>\n

    PROJECT 8D<\/strong>
    \nHow many people live in our country?
    \nProject: Design a Class Census and Give an Estimation Test
    \n\"Envision<\/p>\n

    Lesson 8.1 Addition Properties<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    Olivia arranges cups of buttons on three trays. She records the number of buttons on each cup. Which tray has the most buttons? Use place-value blocks or drawings to help solve the problem.<\/p>\n

    \"Envision
    \nAre you making the same calculations more than once? How can you use structure to help solve the problem?
    \n\"Envision<\/p>\n

    Look Back!<\/strong> Olivia pours all the buttons on Tray A into a bowl. She then divides the buttons equally into 8 cups. How many buttons are in each cup? Explain.<\/p>\n

    \"Math<\/p>\n

    Visual Learning Bridge<\/strong><\/p>\n

    Essential Question<\/strong>
    \nWhat Are Some Properties of Addition?<\/p>\n

    A.<\/strong>
    \nYou can use properties of addition to join groups.<\/p>\n

    Parentheses show what to do first.
    \n\"Envision<\/p>\n

    Associative (Grouping) Property of Addition: You can group addends in any way and the sum will be the same.
    \n\"Envision<\/p>\n

    \u0412.<\/strong>
    \nCommutative (Order) Property of Addition: You can add numbers in any order and the sum will be the same.
    \n\"Envision
    \n57 + 35 = 35 + 57<\/p>\n

    C.<\/strong>
    \nIdentity (Zero) Property of Addition: The sum of zero and any number is that same number.
    \n\"Envision
    \n39 + 0 = 39<\/p>\n

    Convince Me!<\/strong>
    \nUse Structure<\/strong> Pick one of the properties above. Explain how you can use a number line to show an example of that property.<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nRalph says he can rewrite (4 + 5) + 21 as 9 + 21. Do you agree? Why or why not?
    \nAnswer:
    \nYes I\u00a0 agree
    \nbecause 4 + 5 = 9
    \nSo, In place of 4 + 5, we can write has 9<\/p>\n

    Question 2.
    \nWhat property is shown with this equation? How do you know?
    \n65 + (18 + 38) = (18 + 38) + 65
    \nAnswer:
    \nThis equation is in the form of Associative property. This property allows us to change the groupings of addition or multiplication and keep the same value.<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    In 3 and 4, identify each property.<\/p>\n

    Question 3.
    \n4 + (15 + 26) = (4 + 15) + 26
    \nAnswer:
    \nThe equation is in the form of Associative property.<\/p>\n

    Associative property allows us to change groupings of addition or multiplication and keeps the same value.<\/p>\n

    Question 4.
    \n17 + 0 = 17
    \nAnswer:
    \nThis equation is in the form of the Identity property of addition.<\/p>\n

    The identity property of 1 says that any number multiplied by 1 keeps its identity.<\/p>\n

    In 5-7, write each missing number.<\/p>\n

    Question 5.
    \n__ + 90 = 90
    \nAnswer:
    \n0 + 90 = 90<\/p>\n

    Question 6.
    \n42 + 23 = 23 + __
    \nAnswer:
    \n42 + 23 = 23 + 42<\/p>\n

    Question 7.
    \n(2 + __) + 36 = 2 + (23 + 36).
    \nAnswer:
    \n(2 + 23) + 36 = 2 + (23 + 36)<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 8-11, identify each property.<\/p>\n

    Question 8.
    \n19 + 13 = 13 + 19
    \nAnswer:
    \nThe equation is in the form of
    \na + b = b + a
    \nIt is a commutative property.<\/p>\n

    Commutative property states that the change in the order of numbers in the addition or multiplication operation does not change the sum or the product.<\/p>\n

    Question 9.
    \n<\/span>18 + 0 = 18
    \nAnswer:
    \nIt is a identity property.<\/p>\n

    The identity property of 1 says that any number multiplied by 1 keeps its identity.<\/p>\n

    Question 10.
    \n16 + (14 + 13) = (16 + 14) + 13
    \nAnswer:
    \nThe equation is in the form of Associative property.This allows us to change groupings of addition or multiplication and keep the same value.<\/p>\n

    Question 11.
    \n(39 + 12) + 8 = (12 + 39) + 8
    \nAnswer:
    \nThe equation is in the form of the commutative property.<\/p>\n

    Commutative property states that the change in the order of numbers in an addition or multiplication and keeps the same value.<\/p>\n

    In 12-19, write each missing number.<\/p>\n

    \"Math<\/p>\n

    Question 12.
    \n25 + 62 = __ + 25
    \nAnswer:
    \n25 + 62 = 62 + 25
    \nThus the missing number is 62.<\/p>\n

    Question 13.
    \n(22 + 32) + 25 = ___ + (22 + 32)
    \nAnswer:
    \n(22 + 32) + 25 = 25 + (22 + 32)
    \nThus the missing number is 25.<\/p>\n

    Question 14.
    \n23 + __ + 11 = 23 + 11
    \nAnswer:
    \n23 + 0 + 11 = 23 + 11
    \nThus the missing number 0.<\/p>\n

    Question 15.
    \n10 + (45 + 13) = (__ + 45) + 13
    \nAnswer:
    \n10 + ( 45 + 13 ) = (10 + 45) + 13
    \nThus the missing number is 10.<\/p>\n

    Question 16.
    \n(__ + 0) + 14 = 7 + 14
    \nAnswer:
    \n(7 + 0) + 14 =\u00a0 7 + 14
    \nThus the missing number is 7.<\/p>\n

    Question 17.
    \n(12 + 2) + 20 = ___+ 20
    \nAnswer:
    \n(12 + 2) + 20 = 14 + 20
    \nThus the missing number is 14.<\/p>\n

    Question 18.
    \n34 + (2 + 28) = (___ + 28) + 34
    \nAnswer:
    \n34 + (2 + 28) = ( 2 + 28 ) + 34
    \nThus the missing number is 2.<\/p>\n

    Question 19.
    \n(50 + 30) + __ = 50 + (30 + 20)
    \nAnswer:
    \n(50 + 30) + 20 = 50 + (30 + 20)
    \nThus the missing number is 20.<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Question 20.
    \nMake Sense and Persevere<\/strong> Gino packs his blue and green pencils into boxes. He puts 8 pencils in each box. How many boxes does Gino use?
    \n\"Envision
    \nAnswer:
    \nBlue pencils = 23
    \nGreen pencils =17
    \nGino puts pencils in each box = 8
    \nBlue pencils + Green pencils = 40
    \nTherefore 40 \u00f7 5 = 5
    \nGino uses 5 boxes.<\/p>\n

    Question 21.
    \nGroup the addends below in a different way to get the same sum. Write the new equation.
    \n(42 + 14) + 6 = 62
    \nAnswer:
    \nNew equation is\u00a0 (6+ 14) + 42 = 62<\/p>\n

    Question 22.
    \nVocabulary<\/strong> How is the Commutative Property of Addition like the Commutative Property of Multiplication?
    \nAnswer:
    \nThe commutative property states that the numbers on which we operate can be moved from their position without making any difference to the answer.
    \nThe property holds for addition and multiplication.<\/p>\n

    Question 23.
    \nenVision\u00ae STEM<\/strong> A lionfish has 13 spines on its back, 2 more spines near its stomach, and 3 more near its tail. Using a property of add isition, write two different equations to find how many spines a lionfish has. What property did you use?
    \nAnswer:
    \nLionfish has spines on its back = 13
    \nMore spines near it’s stomach = 2
    \n<\/span>More near it’s tail = 3
    \nTo find the total spines on lionfish we are using two different properties of addition.
    \n1. Associative property of addition
    \n(13 + 2) + 3 = 13 + (2 + 3)
    \n2. Commutative property of addition
    \n13 + 2 + 3 = 3 + 2 + 13
    \nTotal spines on lionfish = 18<\/span><\/p>\n

    Question 24.
    \nHigher Order Thinking<\/strong> Barry says he can subtract numbers in any order and the difference will stay the same. Is Barry correct? Give an example to support your answer.
    \nAnswer: No
    \n3 – 2 = 1
    \n2 – 3 = -1
    \nBy this example, we can say that the subtraction of numbers in any order will not be the same.<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 25.
    \nUse place value to find the sum of 33 +42 + 17.
    \nA. 89
    \nB. 90
    \nC. 91
    \nD. 92
    \nAnswer:
    \nD is the answer because
    \n33 + 42 + 17 = 92\u00a0<\/span><\/p>\n

    \"Math<\/p>\n

    Question 26.
    \nUse properties of operations to find the sum of 22 + 30 + 28.
    \nA. 80
    \nB. 70
    \nC. 60
    \nD. 50
    \nAnswer:
    \nTo find the sum of 22 + 30 + 28 we are using commutative property.
    \nWe write the as
    \n22 + 28 + 30; 30 + 28 +\u00a0 30,
    \nFrom this equation, we can calculate 22,28 in an easy way.<\/p>\n

    Lesson 8.2 Algebra: Addition Patterns<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    Shade three sums that are next to each other on the addition table. Add the first and third sums you shaded. Find a pattern using that total and the second sum you shaded. How are the total and the second sum related? Is this true for other sets of three sums next to each other?<\/p>\n

    You can look for relationships in the addition table. The numbers in the shaded column and shaded row are addends. The other numbers are the sums.
    \n\"Envision<\/p>\n

    \"Envision<\/p>\n

    Look Back!<\/strong> Explain how you can test to see if the relationship among the three sums that are next to each other is a pattern.<\/p>\n

    Essential Question<\/strong> How Can You Find Addition Patterns?<\/p>\n

    Visual Learning Bridge<\/strong><\/p>\n

    A.<\/strong>
    \nHelen found the sum of the purple numbers in the red square. Then she found the sum of the green numbers. The sums form a pattern. Find the sums and describe the pattern.
    \n\"Envision
    \nYou can use a variety of strategies to find the sums!
    \n\"Envision<\/p>\n

    B.<\/strong>
    \nUse the Associative Property.
    \n44 + 48 = 44 + (2 + 46)
    \n= (44 + 2) + 46
    \n= 46 + 46<\/p>\n

    C.<\/strong>
    \nUse mental math.
    \n44 +48 = (44 + 2) + (48 \u2013 2)
    \n= 46 +46
    \n44 +48 = 46 + 46<\/p>\n

    The sum of the purple numbers is equal to the sum of the green numbers. That’s a pattern!
    \n\"Envision<\/p>\n

    D.<\/strong>
    \nUse the Commutative and Associative Properties.
    \n44 + 48 = (10 + 34) + (12 + 36)
    \n46 + 46 = (12 + 34) + (10 + 36)
    \nUse the properties to rearrange the addends.
    \n(10 + 34) + (12 + 36) = (10 + 34) + (12 + 36)
    \nThe sum of the purple numbers is 92.
    \nThe sum of the green numbers is 92.
    \nThe sums are double the middle number in the red square. That is another pattern.<\/p>\n

    Convince Me!<\/strong>
    \nGeneralize<\/strong> The red square above is 3 squares tall by 3 squares wide. Sebastian says there are other size squares in the addition table that have patterns. Describe a different-size square and its patterns.<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nAre the sums of any two sets of diagonal corner numbers in a 3-by-3 square in a standard addition table always equal? Explain.
    \nAnswer: Yes<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    Question 2.
    \nLook at the addition table in Box A on the previous page. Why do the numbers going down to the right on the diagonal increase by 2? Explain.
    \nAnswer: In the box A the numbers from left to right is sequence numbers so, in the diagonal box the numbers are going from down to right.<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 3 and 4, use the table at the right.<\/p>\n

    Question 3.
    \nLook at the sums that are shaded the same color. Describe a pattern shown by these pairs of sums. Explain why this pattern is true.
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 4.
    \nFind other pairs of sums with a similar pattern. Shade them on the table. Explain why you chose those sums.<\/p>\n

    In 5 and 6, use the table at the right.<\/p>\n

    Question 5.
    \nShade the table to show a pattern you see. Describe your pattern.
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 6.
    \nExplain why your pattern is true.
    \nAnswer:<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Question 7.
    \nLook for Relationships<\/strong> Greg drew a rectangle on the addition table at the right. He colored the corners. Find the sum of the green corners. Find the sum of the orange corners. What pattern do you notice?
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 8.
    \nDraw another rectangle on the addition table. See if Greg’s pattern is true for this rectangle.
    \nAnswer:<\/p>\n

    Question 9.
    \nExplain why Greg’s pattern works.
    \nAnswer:<\/p>\n

    Question 10.
    \nWhich multiplication fact does the number line show? Write a related division fact.
    \n\"Envision
    \nAnswer:
    \nmultiple of 5.<\/p>\n

    Question 11.
    \nHigher Order Thinking<\/strong> Pierre made an addition table. He skip counted by 3 for the addends. Find and describe a pattern in Pierre’s table.
    \n\"Envision
    \nAnswer:<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 12.
    \nLook at the shaded cells\u00a0 the addition table below.
    \n\"Envision
    \nWhich pattern and property of operations are shown in the shaded cells?
    \nA. Each orange sum is equal to zero plus the other addend; The Identity Property of Addition
    \nB. Each green sum is 10 greater than one of its addends; The Identity Property of Addition
    \nC. Each green sum is ten greater than the sum before; The Associative Property of Addition
    \nD. There are no patterns or properties.
    \nAnswer:<\/p>\n

    Lesson 8.3 Mental Math: Addition<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    A school store sold 436 pencils last week and 7 packages that each had 4 pencils today. Use mental math to find how many pencils were sold in all. Explain how you found your answer.<\/p>\n

    You can use structure by examining the quantities in the problem.
    \n\"Envision<\/p>\n

    Look Back!<\/strong> What is another way you can find the sum of 436 pencils plus 7 packages of 4 pencils each using mental math?<\/p>\n

    Visual Learning Bridge<\/strong><\/p>\n

    Essential Question<\/strong>
    \nHow Can You Add with Question Mental Math?<\/p>\n

    A.<\/strong>
    \nDr. Gomez recorded the number of Northern Right Whales, Atlantic Spotted Dolphins, and Western Atlantic Harbor Seals she saw off the coast of Florida in two different years. How many whales did Dr. Gomez see during the two years?
    \n\"Envision
    \nYou can use an open number line, mental math strategies, and properties of operations to solve this problem.
    \n\"Envision
    \nB.<\/strong>
    \nOne Way<\/strong> Find 325 + 114. Use the adding on strategy.
    \n\"Envision
    \nStart at 325. Break apart 114.
    \nAdd 100 to 325.
    \nAdd 10 to 425.
    \nAdd 4 to 435.
    \n325 + 114 = 439
    \nDr. Gomez saw 439 whales.<\/p>\n

    C.<\/strong>
    \nAnother Way<\/strong>
    \nFind 325 + 114. Use the make ten strategy. Break apart
    \n114. 114 = 5 + 100 + 9
    \nAdd 5 to 325 to make ten.
    \n325 + 5 = 330
    \nThen, add 100.
    \n330 + 100 = 430
    \nBreak 114 apart to find a number that makes a ten when added to 325.
    \n\"Envision
    \nFinally, add 9.
    \n430 + 9 = 439
    \n325 + 114 = 439
    \nDr. Gomez saw 439 whales.<\/p>\n

    Convince Me!<\/strong>
    \nModel with Math<\/strong> Show two ways to find the total number of dolphins seen.<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nCompare the One Way and on the previous page. How are they the same? How are they different?<\/p>\n

    Question 2.
    \nUse mental math to find how many animals Dr. Gomez saw during Year 2. Show your work.
    \nAnswer:
    \nDr.Gomez saw whales in second year = 114
    \nD<\/span>r.Gomez saw Dolphins in second year = 171
    \n<\/span>Dr. Gomez saw seals in second year = 212
    \nTotal number of animals that Dr.Gomez saw during second year is
    \n114 + 171 +212
    \n100 + 10 + 4 + 100 + 70 + 1 + 200 + 10 + 2
    \n400 + 90 + 5 + 2
    \n400 + 90 + 7
    \n400 + 97 = 497<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    Question 3.
    \nUse the make ten strategy to add 738 + 126.
    \n126 = 2 + 24 + 100
    \n738 + ___ = 740
    \n740 + __ = 764
    \n764 + __ = 864
    \nSo, 738 + 126 = ___.
    \nAnswer:
    \n126 = 2 + 24 + 100
    \n738 + 2 = 740
    \n740 + 24 = 764
    \n764 + 100 = 864
    \nSo, 738 + 126 = 864<\/p>\n

    Question 4.
    \nUse the adding\u00a0 strategy to add 325 + 212.
    \n212 = 200 + 10 + 2
    \n325 + 200 = ___
    \n525 + 10 = ___
    \n___ + 2 = 537
    \nSo, 325 + 212 = __.<\/p>\n

    Answer:
    \n212 = 200 + 10 + 2
    \n325 + 200 = 525
    \n525 + 10 = 535
    \n535 + 2 = 537
    \nSo, 325 + 212 = 537<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 5-12, find each sum using mental math or an open number line.<\/p>\n

    Question 5.
    \n252 +44
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n252 + 44
    \n200 + 50 + 2 + 40 + 4
    \n200 + 90 + 6
    \n200 + 96 = 296<\/p>\n

    Question 6.
    \n<\/span>236 + 243
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n236 + 243
    \n200 + 30 + 6 + 200 +40 + 3
    \n400 + 70 + 9
    \n400 + 79 = 479<\/p>\n

    Question 7.
    \n651 + 150
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n<\/span>651 + 150
    \n600+ 50 + 1 +100 + 50
    \n700 + 100 + 1
    \n600 + 1 = 601<\/p>\n

    Question 8.
    \n378 + 542
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n378 + 542
    \n300 + 70 + 8 + 500 + 40 + 2
    \n800 + 110 + 10
    \n800 + 120 = 920<\/p>\n

    Question 9.
    \n473 + 198
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n473 + 198
    \n400 + 70 + 3 + 100 + 90 + 8
    \n500 + 160 + 11
    \n500 + 171 = 671<\/p>\n

    Question 10.
    \n319 + 339
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n319 + 339
    \n300 + 10 + 9 + 300 + 30 + 9
    \n600 + 40 + 18
    \n600 + 58 = 658<\/p>\n

    Question 11.
    \n208 + 511
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n208 + 511
    \n200 + 8 + 500 + 10 + 10 + 1
    \n700 + 18 + 10 +1
    \n710 + 19 = 729<\/p>\n

    Question 12.
    \n523 + 169
    \nAnswer:
    \nTo find the sum here we are using mental math.
    \n523 + 169
    \n500 + 20 + 3 + 100 + 60 + 9
    \n600 + 80 + 12
    \n600 + 92 = 692<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Question 13.
    \nHigher Order Thinking<\/strong> Maxine earns $8 each hour that she works as a cashier. She starts with $233. Today she cashiers for 6 hours. How much does she have at the end of the day? Explain how you found your answer.
    \nAnswer:
    \nGiven,
    \nMaxine earns $8 each hour that she works as a cashier.
    \nShe starts with $233. Today she cashiers for 6 hours.
    \n6 \u00d7 $8 = $48
    \n$233 + $48 = $281
    \nTherefore Maxine have $281 at the end of the day.<\/p>\n

    Question 14.
    \nLauren sorted the 4 solids into 2 groups. Use mathematical terms to explain how she sorted the solids.
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 15.
    \nThe Rodriguez family drives 229 miles on Friday and 172 miles on Saturday. Explain how you can use the adding on strategy to find the total number of miles the Rodriguez family drives.
    \nAnswer:
    \nRodriguez family drives on Friday = 229 miles
    \nRodriguez family drives on Saturday = 172
    \nTotal number of miles that Rodriguez family drives = 229 + 172
    \n200 + 20 + 9 + 100 + 70 + 2
    \n300 + 90 + 11
    \n300 + 101 = 401<\/p>\n

    Question 16.<\/span><\/p>\n

    Critique Reasoning<\/strong> Bill added 438 + 107. He recorded his reasoning below. Critique Bill’s reasoning. Are there any errors? If so, explain the errors.
    \nFind 438 + 107.
    \nI’ll think of 7 as 2 + 5.
    \n438 + 2 = 440
    \n440 + 7 = 447
    \n447 + 100 = 547
    \nSo, 438 + 107 is 547.
    \nAnswer:
    \nAbove equation has an error, In place of adding 7 with 440\u00a0 we want to add 5 then it is correct.<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 17.
    \nFind 153 + 121. Break apart 121 by place value, and then use the adding on strategy. Select numbers to complete the equations.
    \n\"Envision
    \nAnswer:
    \n\"Envision-Math-Common-Core-Grade-3-Answer-Key-Topic-8-Use-Strategies-and-Properties-to-Add-and-Subtract-69.3\"<\/p>\n

    Question 18.
    \nFind 123 + 176. Break apart 176 by place value, and then use the adding on strategy. Select numbers to complete the equations.
    \n\"Envision
    \nAnswer:
    \n\"Envision-Math-Common-Core-Grade-3-Answer-Key-Topic-8-Use-Strategies-and-Properties-to-Add-and-Subtract-69.4\"<\/p>\n

    Lesson 8.4 Mental Math: Subtraction<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    Peyton wants to buy one item that costs $425 and another item that costs $210. If she gets the discount shown on the sign below, what is the sale price? Explain how you can use mental math to find your answer.
    \n\"Envision<\/p>\n

    Even when you use mental math, you can still show your work! You can construct arguments using mental math.
    \n\"Envision<\/p>\n

    Look Back!<\/strong> What is another way you can use mental math to solve the problem?<\/p>\n

    Visual Learning Bridge<\/strong><\/p>\n

    Essential Question<\/strong>
    \nHow Can You Subtract with Mental Math?<\/p>\n

    A.<\/strong>
    \nA store is having a sale on jackets. A jacket is on sale for $197 less than the original price. What is the sale price?
    \n\"Envision<\/p>\n

    You can use mental math and the relationship between addition and subtraction to solve this problem.
    \n\"Envision
    \nThe difference is the answer when subtracting two numbers.<\/p>\n

    B.<\/strong>
    \nOne Way<\/strong>
    \nCount Back on the Number Line Find 352 \u2013 197.
    \nTo subtract 197 on an open number line, you can subtract 200, and then add 3.
    \n352 – 200 = 152
    \n152 + 3 = 155
    \n\"Envision
    \nSo, 352 \u2013 197 = 155. The sale price is $155.<\/p>\n

    C.<\/strong>
    \nAnother Way<\/strong>
    \nCount Up on the Number Line
    \nFind 352 \u2013 197.
    \nTo find 352 \u2013 197, you can think addition: 197 + ? = 352
    \n197 + 3 = 200
    \n200 + 100 = 300
    \n300 + 52 = 352
    \nAddition and subtraction are inverse operations.
    \n\"Envision
    \n3+ 100 + 52 = 155
    \n197 + 155 = 352, so 352 \u2013 197 = 155.
    \nThe sale price is $155.<\/p>\n

    Convince Me! Construct Arguments<\/strong> Which of the two ways above would you use to solve 762 \u2013 252? Explain.<\/p>\n

    Another Example!<\/strong>
    \nYou can make a simpler problem to find 352 \u2013 197.
    \nAdd 3 to both numbers.
    \n352 + 3 = 355 and 197 + 3 = 200.
    \nThen you have 355 \u2013 200.
    \nSo, 355 \u2013 200 = 155 and 352 \u2013 197 = 155.<\/p>\n

    If you get stuck using one strategy, another strategy may be easier!
    \n\"Envision<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nIn the One Way example on the previous page, why do you add 3 to 152 instead of subtracting 3 from 152?
    \nAnswer: We have to add or subtract the same numbers for making the correct answer.<\/p>\n

    Question 2.
    \nSuppose a computer costs $573. If you buy it today, it costs $498. What is the discount? Show your work.
    \nAnswer:
    \nGiven,
    \nSuppose a computer costs $573. If you buy it today, it costs $498.
    \n$573 – $498 = $92
    \nThus the discount is $92.<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    In 3-6, solve using mental math.<\/p>\n

    Question 3.
    \n846 \u2013 18
    \n848 \u2013 20 =___
    \nAnswer:
    \n846 – 18
    \n848 – 20
    \n800 + 40 + 8 – 20
    \n800 + 48 – 20
    \n848 – 20 = 828<\/p>\n

    Question 4.
    \n534 \u2013 99
    \n535 \u2013 100 = __
    \nAnswer:
    \n534 – 99
    \n535 – 100
    \n500 + 30 + 5 – 100
    \n500 + 35 – 100
    \n535 – 100 = 435<\/p>\n

    Question 5.<\/span><\/p>\n

    873 \u2013 216
    \n877 \u2013 220 = ___
    \nAnswer:
    \n873 – 216
    \n877 – 220
    \n800 + 70 + 7 – 200 + 20
    \n800 + 77 – 220
    \n877 – 220 = 657<\/p>\n

    Question 6.
    \n782 \u2013 347
    \n785 \u2013 350 = ___
    \nAnswer:
    \n782 – 347
    \n785 – 350
    \n700 + 80 + 5 – 300 + 50
    \n700 + 85 – 350
    \n785 – 350 = 435<\/p>\n

    Question 7.
    \nFind 400 \u2013 138 using the make ten strategy
    \n138 + __ = 140
    \n140 + ___ = 200
    \n200 + __ = 400
    \n___ + __ + ___ = ___
    \nAnswer:
    \n138 + 2 = 140
    \n140 + 60 = 200
    \n200 + 200 = 400
    \n2 + 60 + 200 = 262<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 8-15, use an open number line or the think addition strategy to find each difference.<\/p>\n

    Question 8.
    \n128 \u2013 19
    \nAnswer: 109<\/p>\n

    Question 9.
    \n887 \u2013 18
    \nAnswer: 869<\/p>\n

    Question 10.
    \n339 \u2013 117
    \nAnswer: 222<\/p>\n

    Question 11.
    \n468 \u2013 224
    \nAnswer: 244<\/p>\n

    Question 12.
    \n784 \u2013 515
    \nAnswer: 269<\/p>\n

    Question 13.
    \n354 \u2013 297
    \nAnswer: 57<\/p>\n

    Question 14.
    \n853 \u2013 339
    \nAnswer: 514<\/p>\n

    Question 15.
    \n638 \u2013 372
    \nAnswer: 266<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Question 16.
    \nSarah has $350. How much money will she have after buying the computer at the sale price?
    \n\"Envision
    \nAnswer:
    \nGiven,
    \nSarah has $350.
    \n$350 – $58 = $292<\/p>\n

    Question 17.
    \nModel with Math<\/strong> Jessica has an array with 9 columns. There are 36 counters in the array. How many rows does her array have? Show how to represent the problem and find the answer.
    \nAnswer:
    \nGiven,
    \nJessica has an array with 9 columns.
    \nThere are 36 counters in the array.
    \n9 \u00d7 4 = 36
    \nThus there are 4 rows and 9 columns.<\/p>\n

    Question 18.
    \nOf the students at Paul’s school, 270 are girls and 298 are boys. There are 354 students at Alice’s school. How many more students are there at Paul’s school than at Alice’s school?
    \nAnswer:
    \nGirls at Paul’s school = 270
    \nBoys at Paul’s school = 298
    \nStudents at Alice’s school = 354
    \nStudents at Paul’s school = 568
    \n568 – 354 = 214
    \nPaul’s school has 214 students more than Alice’s school students.<\/p>\n

    Question 19.
    \nHigher Order Thinking<\/strong> To find 357 \u2013 216, Tom added 4 to each number and then subtracted. Saul added 3 to each number and then subtracted. Will both ways work to find the correct answer? Explain.
    \nAnswer:
    \nTo find 357 \u2013 216, Tom added 4 to each number and then subtracted.
    \n357+4 = 361
    \n216 + 4 = 220
    \n361 – 220 = 141
    \nSaul added 3 to each number and then subtracted.
    \n357+3 = 360
    \n216 + 3 = 219
    \n360 – 219 = 141<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 20.
    \nUse the relationship between addition and subtraction to find 233 \u2013 112. Select numbers from the box to complete the work on the open number line and the equations.
    \n\"Envision
    \nAnswer:
    \n\"Envision-Math-Common-Core-3rd-Grade-Answers-Topic-8-Use-Strategies-and-Properties-to-Add-and-Subtract-72.3\"<\/p>\n

    Lesson 8.5 Round Whole Numbers<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong>
    \nThink about ways to find numbers that tell about how much or about how many. Derek has 277 stickers. What number can you use to describe about how many stickers Derek has? Explain how you decided.<\/p>\n

    Think about whether you need to be precise.
    \n\"Envision<\/p>\n

    Look Back!<\/strong> Derek gets 3 more packages of 10 stickers. About how many stickers does Derek have now?<\/p>\n

    Essential Question<\/strong>
    \nHow Can You Round Numbers?<\/p>\n

    Visual Learning Bridge<\/strong><\/p>\n

    A.<\/strong>
    \nAbout how many rocks does Tito have? Round 394 to the nearest ten.<\/p>\n

    Place value is the value of the place a digit has in a number. Think about the place value of the digits in 394.
    \n\"Envision<\/p>\n

    When you round to the nearest ten, you are finding the closest multiple of ten for a given number.
    \n\"Envision<\/p>\n

    \"Envision<\/p>\n

    B.<\/strong>
    \nYou can use place-value understanding and a number line to round to the nearest ten.
    \n\"Envision
    \n394 is closer to 390 than 400, so 394 rounds to 390.
    \nTito has about 390 rocks.<\/p>\n

    C.<\/strong>
    \nAbout how many rocks does Donna have? Round 350 to the nearest hundred.
    \n\"Envision
    \nIf a number is halfway between, round to the greater number
    \n350 is halfway between 300 and 400, so 350 rounds to 400.
    \nDonna has about 400 rocks.<\/p>\n

    Convince Me! Make Sense and Persevere<\/strong> Susan says, \u201cI am thinking of a number that has a four in the hundreds place and a two in the ones place. When you round it to the nearest hundred, it is 500.\u201d What number could Susan be thinking of? What other numbers could be Susan’s number?<\/p>\n

    Another Example<\/strong>
    \nAbout how many rocks does Carl have? Round 345 to the nearest ten and hundred.
    \nRound to the nearest ten.
    \n345 is halfway between 340 and 350, so 345 rounds to 350.
    \n\"Envision
    \nRound to the nearest hundred.
    \n345 is closer to 300 than 400, so 345 rounds to 300.
    \n\"Envision<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nWhat number is halfway between 200 and 300?
    \nAnswer:
    \nThe halfway between 200 and 300 is 250.<\/p>\n

    Question 2.
    \nSheri rounds 678 to 680. What place does she round to?
    \nAnswer:<\/p>\n

    Here the digits in the one’s place is\u00a0 8 in 678, now round to the nearest multiple of 10 which is greater than the number.
    \nGiven,
    \nSheri rounds 678 to 680.
    \nThe nearest ten to 678 is 680.<\/p>\n

    Question 3.
    \nTito adds one more rock to his collection on the previous page. About how many rocks does he have now, rounded to the nearest ten? Rounded to the nearest hundred? Explain.
    \nAnswer:<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    In 4-6, round to the nearest ten.<\/p>\n

    Question 4.
    \n\"Envision
    \nAnswer: 517 to the nearest ten is 520.<\/p>\n

    Question 5.
    \n149
    \nAnswer:<\/p>\n

    Here the digits in the one’s place of 149 is 9 , now round to the nearest multiple of 10 which is greater than the number.
    \n149 to the nearest ten is 150.<\/p>\n

    Question 6.
    \n732
    \nAnswer:<\/p>\n

    Here the digits in the one’s place of 732 is 2, now round to the nearest multiple of 10<\/p>\n

    732 to the nearest ten is 730.<\/p>\n

    In 7-9, round to the nearest hundred.<\/p>\n

    Question 7.
    \n\"Envision
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred, look at the ten’s digit. If the numbers is 0,1,2,3,4 you will round to previous hundred.<\/p>\n

    640 to the nearest hundred is 600.<\/p>\n

    Question 8.
    \n305
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred, look at the ten’s digit. If the numbers is 0,1,2,3,4 you will round to the previous hundred.<\/p>\n

    305 to the nearest hundred is 300.<\/p>\n

    Question 9.
    \n166
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred , look at the ten’s digit.If the numbers is 5,6,7,8,9 you will round to the next hundred.<\/p>\n

    166 to the nearest hundred is 200.<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 10-12, round to the nearest ten.<\/p>\n

    Question 10.
    \n88
    \nAnswer:<\/p>\n

    Here the digits in the one’s place of 88 is 8 , now round to the nearest multiple of 10 which is greater than the number.
    \n88 to the nearest ten is 90.<\/p>\n

    Question 11.
    \n531
    \nAnswer:<\/p>\n

    Here the digits in the one’s place of 531 is 1, now round to the nearest multiple of 10 which is less than the number.
    \n531 to the nearest ten is 530.<\/p>\n

    Question 12.
    \n855
    \nAnswer:<\/p>\n

    Here the digits in the one’s place of 855 is 5, now round to the nearest multiple of 10 which is greater than the number.
    \n855 to the nearest ten is 860.<\/p>\n

    In 13-15, round to the nearest hundred.<\/p>\n

    Question 13.
    \n428
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred, look at the ten’s digit of the number.If the numbers are 0,1,2,3,4, you will round down to the previous hundred.<\/p>\n

    428 to the nearest hundred is 400.<\/p>\n

    Question 14.
    \n699
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred look at the ten’s digit of the given number.If the digits are 5,7,8,9 you will round to the previous hundred.<\/p>\n

    699 to the nearest hundred is 700.<\/p>\n

    Question 15.
    \n750
    \nAnswer: when rounding to the nearest hundred, look at the ten’s digit of the number. If the digits are 5,6,7,8,9 you will round to the next hundred.<\/p>\n

    750 to the nearest hundred is 700. or 800.<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Question 16.
    \nThe Leaning Tower of Pisa in Italy has 294 steps. To the nearest ten, about how many steps are there? To the nearest hundred, about how many steps are there?
    \n\"Envision
    \nAnswer:
    \nGiven,
    \nThe Leaning Tower of Pisa in Italy has 294 steps.
    \n294 to the nearest ten is 290.
    \n294 to the nearest hundred is 300.
    \nThus there are about 300 steps.<\/p>\n

    Question 17.
    \nCritique Reasoning<\/strong> Zoe says 247 rounded to the nearest hundred is 300 because 247 rounds to 250 and 250 rounds to 300. Is Zoe correct? Explain.
    \nAnswer:
    \nZoe says 247 rounded to the nearest hundred is 300 because 247 rounds to 250 and 250 rounds to 300.
    \n247 rounded to the nearest hundred is 200.
    \nSo, Zoe is not correct.<\/p>\n

    Question 18.
    \nUse the number line to show a number that rounds to 200 when it is rounded to the nearest ten.
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 19.
    \nName the least number of coins you can use to show $0.47. What are the coins?
    \nAnswer:<\/p>\n

    Question 20.
    \nSuppose you are rounding to the nearest hundred. What is the greatest number that rounds to 600? What is the least number that rounds to 600?
    \nAnswer:
    \nThe greatest number that round 600 to the nearest 100 would be 600 + 50 – 1 = 649. It won’t be 650 because of 650 rounds to 700.<\/p>\n

    Question 21.
    \nHigher Order Thinking<\/strong> A 3-digit number has the digits 2,5, and 7. To the nearest hundred, it rounds to 800. What is the number? Show how you found the answer.
    \nAnswer:
    \nFor the number to be rounded off to 800, it needs to be either 750 or above or 850 and below.
    \nWith the given numbers, we can only have the following combinations:
    \n257~300
    \n275~300
    \n527~500
    \n572~600
    \n725~700
    \n752~800
    \nAnd hence, 752 is the only combination of numbers that fits.<\/p>\n

    Question 22.
    \nEmil says, \u201cI am thinking of a number that is greater than 142, rounds to 100 when rounded to the nearest hundred, and has a 5 in the ones place.” What is Emil’s number?<\/p>\n

    What else can you try if you get stuck?
    \n\"Envision
    \nAnswer: 542<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 23.
    \nSelect all the numbers that will equal $100 when rounded to the nearest hundred.
    \n\"Envision $10
    \n\"Envision $110
    \n\"Envision $ 89
    \n\"Envision $150
    \n\"Envision $91
    \nAnswer:
    \n$110, $89, $91 are rounded to the nearest hundred.<\/p>\n

    Question 24.
    \nSelect all the numbers that will equal 70 when rounded to the nearest ten.
    \n\"Envision 62
    \n\"Envision 75
    \n\"Envision 72
    \n\"Envision 83
    \n\"Envision 73
    \nAnswer:
    \nThe number 70 rounded to the nearest ten is 75, 72, 73.<\/p>\n

    Lesson 8.6 Estimate Sums<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    Look at the table below. Is the mass of a female and male sun bear together more or less than the mass of one female black bear? Without finding an exact answer, explain how you can decide.<\/p>\n

    \"Envision You can use symbols, numbers, and words to be precise in your explanation.<\/p>\n

    Look Back!<\/strong> Why is an exact answer not needed to solve the problem?<\/p>\n

    Essential Question<\/strong>
    \nHow Can You Estimate Sums?<\/p>\n

    Visual Learning Bridge<\/strong><\/p>\n

    A.<\/strong>
    \nDo the two pandas together weigh more than 500 pounds?
    \nEstimate 255 + 329.
    \n\"Envision<\/p>\n

    You can estimate to find about how much the two pandas weigh.
    \n\"Envision<\/p>\n

    B.<\/strong>
    \nOne Way<\/strong>
    \nRound to the nearest hundred.
    \n\"Envision
    \n255 + 329 is about 600.
    \n600 > 500
    \nThe pandas together weigh more than 500 pounds.<\/p>\n

    C.<\/strong>
    \nAnother Way<\/strong>
    \nUse compatible numbers.
    \n\"Envision
    \nCompatible numbers are numbers that are close to the addends, but easy to add mentally
    \n\"Envision
    \n255 + 329 is about 575 and 575 > 500.
    \nThe total weight is more than 500 pounds.<\/p>\n

    Convince Me! Be Precise<\/strong> Sandy said, “Just look at the numbers. 200 and 300 is 500. The pandas weigh over 500 pounds because one panda weighs 255 pounds and the other weighs 329 pounds.” What do you think she means? Use numbers, words, or symbols to explain.<\/p>\n

    Another Example!<\/strong>
    \nSuppose one panda ate 166 pounds of bamboo in a week and another ate 158 pounds. About how many pounds of bamboo did the two pandas eat?
    \n\"Envision
    \nYou can estimate 166 + 158 by rounding to the nearest ten.
    \n\"Envision
    \nThe pandas ate about 330 pounds of bamboo in a week.<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nTwo addends are rounded to greater numbers. Is the estimate greater than or less than the actual sum?
    \nAnswer:<\/p>\n

    Question 2.
    \nMary and Todd estimate 143 + 286. They have different answers. Can they both be correct? Explain why or why not.
    \nAnswer:
    \nMary and Todd has only one answer that is 143 + 286 = 429<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    Round to the nearest ten to estimate.<\/p>\n

    Question 3.
    \n218 + 466 ___+___= ___
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 218 is 8, now round to the nearest multiple of 10 which is greater than the ten.
    \n218 round to the nearest ten to estimate is 220.<\/p>\n

    The digit in the one’s place of 466 is 6, now round to the nearest multiple of ten which is greater than the number.
    \n466 round to the nearest ten to estimate is 470
    \n220 + 470 = 690<\/p>\n

    Question 4.
    \n108 + 223 ___ + ___ = ____
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 108 is 8, now round to the nearest multiple of 10 which is greater than the number.
    \n108 round to the nearest ten to estimate is 110.<\/p>\n

    The digit in the one’s place of 223 is 3, now round to the nearest multiple of 10 which is less than the number.
    \n223 round to the nearest ten to estimate is 220.
    \n110 + 220 = 330<\/p>\n

    Round to the nearest hundred to estimate.<\/p>\n

    Question 5.
    \n514 + 258 ___ + ___ = ____
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 514 is 4, now round to the nearest multiple of 10 which is less than the number.
    \n514 round to the nearest hundred to estimate is 500.<\/p>\n

    The digit in the one’s place of 258 is round to the nearest ten which is greater than the number.
    \n258 round to the nearest hundred to estimate is 300.
    \n500 + 300 = 800<\/p>\n

    Question 6.
    \n198 + 426 ___ + ___ = ____
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 198 is 8,now round to the nearest multiple of ten which is greater than the number.
    \n198 round to the nearest hundred to estimate is 200.<\/p>\n

    The digit in the one’s place of 426 is 6, now round to the nearest multiple of 10 which is greater than the number.
    \n426 round to the nearest hundred to estimate is 400.
    \n200 + 400 = 600<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 7-10, round to the nearest ten to estimate.<\/p>\n

    Question 7.
    \n138 + 435
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 138 is 8, now round to the nearest multiple of ten which is greater than the number.
    \n138 round to the nearest ten to estimate is 140.<\/p>\n

    The digit in the one’s place of 435 is 5 now round to the nearest multiple of ten which is greater than the number.
    \n435 round to the nearest ten to estimate is 440.
    \n140 + 440 = 580<\/p>\n

    Question 8.
    \n563 + 289
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 563 is 5 now round to the nearest multiple of ten which is less than the number.
    \n563 round to the nearest ten to estimate is 560.<\/p>\n

    The digit in the one’s place of 289 is 9 now round to the nearest multiple of ten which is greater than the number.
    \n289 round to the nearest ten to estimate is 290
    \n560 + 290 = 850<\/p>\n

    Question 9
    \n644 + 172
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of 644 is 4 now round to the nearest multiple of ten which is less than the number.
    \n644 round to the nearest ten to estimate is 640.<\/p>\n

    The digit in the one’s place of 172 is 2, now round to the nearest multiple of ten which is less than the number.
    \n172 round to the nearest ten to estimate is 170
    \n640 + 170 = 810<\/p>\n

    Question 10.
    \n376 + 295
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of the number 376 is 6 now round to the nearest ten which is greater than the number.
    \n376 round to the nearest ten to estimate is 380.<\/p>\n

    The digit in the one’s place of 295 is 5 now round to the nearest multiple of ten which is greater than the number.
    \n295 round to the nearest ten to estimate is 300
    \n380 + 300 = 680<\/p>\n

    In 11-14, round to the nearest hundred to estimate.<\/p>\n

    Question 11.
    \n403 + 179
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred look at the ten’s digit of the number which the number is 0,1,2,3,4 you will round to the previous hundred.
    \n403 round to the nearest hundred to estimate is 400.<\/p>\n

    Here the ten’s place of the 179 is 7 you will round to the next hundred.
    \n179 round to the nearest hundred to estimate is 200.
    \n400 + 200 = 600<\/p>\n

    Question 12.
    \n462 + 251
    \nAnswer:<\/p>\n

    Here the ten’s place of the number is 462 is 6 you will round to the previous hundred.<\/p>\n

    462 round to the nearest hundred to estimate is 500.<\/p>\n

    Here the ten’s place of the number 251 is 5 you will round to the next hundred.
    \n251 round to the nearest hundred to estimate is 300.
    \n500 + 300 = 800<\/p>\n

    Question 13.
    \n274 + 443
    \nAnswer:<\/p>\n

    Here the digit in the ten’s place of 274 is 7 you will round to the next hundred.
    \n274 round to the nearest hundred to estimate is 300.<\/p>\n

    The digit in the ten’s of 443 is\u00a0 4 you will round to the previous hundred.
    \n443 round to the nearest hundred to estimate is 400.
    \n300 + 400 = 700<\/p>\n

    Question 14.
    \n539 + 399
    \nAnswer:<\/p>\n

    The digit in the ten’s place of 539 is 3 you will round to the previous hundred.
    \n539 round to the nearest hundred to estimate is 500.<\/p>\n

    The digit in the ten’s place of 399 is 9 you will round to the next hundred.
    \n399 round to the nearest hundred to estimate is 400.
    \n500 + 400 = 900<\/p>\n

    In 15-18, use compatible numbers to estimate.<\/p>\n

    Question 15.
    \n175 + 126
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply or division mentally.<\/p>\n

    Here 170 and 130 are the compatible numbers to the 175 and 126.
    \n\"Envision<\/p>\n

    Question 16.
    \n167 + 27
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply or division mentally.<\/p>\n

    Here 170 and 30 are the compatible number for 167 and 27.
    \n\"Envision<\/p>\n

    Question 17.
    \n108 + 379
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply or division mentally.<\/p>\n

    Here 110 and 380 are the compatible numbers for 108 and 379.
    \n\"Envision<\/p>\n

    Question 18.
    \n145 + 394
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply or division mentally.<\/p>\n

    Here 150 and 390 are the compatible numbers for 145 and 394.<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Use the table to answer 19 and 20.<\/p>\n

    Question 19.
    \nMs. Tyler drove from Albany to Boston, and then from Boston to Baltimore. To the nearest ten miles, about how many miles did she drive in all?
    \nAnswer:<\/p>\n

    \"Envision<\/p>\n

    Question 20.<\/p>\n

    Ms. Tyler drove from Boston to New York City and back again. To the nearest hundred miles, about how many miles did she drive?<\/span><\/p>\n

    Answer:<\/p>\n

    Given,
    \nMs. Tyler drives from Boston to New York City\u00a0 = 211
    \nMs.Tyler drives back to nearest hundred miles to Boston\u00a0 = 211 – 100
    \n= 111
    \nHow many miles did she drive\u00a0 equals to 211 + 111 = 322<\/p>\n

    Question 21.
    \nReasoning<\/strong> Jen has $236. Dan has $289. Do Jen and Dan have more than $600 in all? Estimate to solve. Explain.
    \nAnswer:
    \nJen has $236
    \nDon has $286
    \nJen and Don has 236 + 289 = 525
    \nNo, They did have more than $600<\/p>\n

    Question 22.
    \nRalph has 75\u00a2. How much more money does he need to buy a pencil for 90\u00a2? Complete the diagram.<\/p>\n

    Answer:
    \nRalph has 75 cents.
    \nHe need to buy a pencil for 90 cents.
    \nRalph need to buy a pencil = 90 cents – 75 cents =15 cents<\/p>\n

    Question 23.
    \nHigher Order Thinking<\/strong> Susan drove 247 miles on Wednesday morning. Then she drove 119 miles on Wednesday afternoon. On Thursday, Susan drove 326 miles. About how far did Susan drive in all? Explain the method you used to estimate.<\/p>\n

    Remember that you learned different estimation strategies.
    \n\"Envision<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 24.
    \nRound to the nearest 10 to estimate the sums.
    \n\"Envision
    \nAnswer:
    \n273 round to the nearest ten to estimate is 270
    \n616 round to the nearest ten to estimate is 620
    \n270 + 620 = 890
    \n542 round to the nearest ten to estimate is 540
    \n338 round to the nearest ten to estimate is 340
    \n540 + 340 = 880
    \n435 round to the nearest ten to estimate is 440
    \n441 round to the nearest ten to estimate is 440
    \n440 – 440 = 0<\/p>\n

    Question 25.
    \nRound to the nearest 100 to estimate the sums.
    \n\"Envision
    \nAnswer:
    \n173 round to the nearest hundred to estimate is 200
    \n139 round to the nearest hundred to estimate is 100
    \n200 – 100 = 100
    \n155 round to the nearest hundred to estimate is 200
    \n177 round to the nearest hundred to estimate is 200
    \n200 – 200 = 0
    \n289 round to the nearest hundred to estimate is 300
    \n18 round to the nearest hundred to estimate is 0
    \n300 – 0 = 300<\/p>\n

    Lesson 8.7 Estimate Differences<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    Sara collected 220 cans on Monday, 80 cans on Tuesday, and 7 cartons with 8 cans each on Wednesday to recycle. Pierre collected 112 cans. About how many more cans did Sara collect than Pierre?<\/p>\n

    You can make sense and persevere. What is a good strategy for solving this problem?
    \n\"Envision<\/p>\n

    Look Back!<\/strong> Which strategy gives an estimate that is closest to the exact answer? How did you decide?<\/p>\n

    Essential Question<\/strong>
    \nHow Can You Estimate Differences?<\/p>\n

    A.<\/strong>
    \nAll of the tickets for a concert were sold. So far, 126 people have arrived at the concert. About how many people who have tickets have not arrived?
    \nEstimate 493 – 126 by rounding.
    \n\"Envision<\/p>\n

    You can estimate to find about how many.
    \n\"Envision<\/p>\n

    B.<\/strong>
    \nOne Way<\/strong>
    \nRound each number to the nearest hundred and subtract.
    \n\"Envision
    \nAbout 400 people have not yet arrived.<\/p>\n

    C.<\/strong>
    \nAnother Way<\/strong>
    \nRound each number to the nearest ten and subtract.
    \n\"Envision
    \nAbout 360 people have not yet arrived.<\/p>\n

    Convince Me! Model with Math<\/strong> Suppose 179 people have arrived at the concert. Estimate how many people have not arrived.<\/p>\n

    Another Example!<\/strong>
    \nYou can use compatible numbers to estimate differences.
    \n\"Envision
    \n375 and 150 are compatible numbers for 372 and 149.
    \n\"Envision<\/p>\n

    Guided Practice<\/strong><\/p>\n

    Do You Understand?<\/strong><\/p>\n

    Question 1.
    \nDoes rounding to the nearest ten or nearest hundred give an estimate closer to the exact answer for 295 \u2013 153?<\/p>\n

    Answer:<\/p>\n

    Here the digit of the one’s place of 295 is 5 now round to the nearest multiple of ten which is greater than the number.
    \n295 round to the nearest ten to estimate is 290<\/p>\n

    The digit in the one’s place of 153 is3 now round to the nearest multiple of ten which is less than the number.
    \n153 round to the nearest ten to estimate is 140
    \n290 – 140 =150<\/p>\n

    Question 2.
    \nA theater sells 408 tickets. Two hundred seventy-three people arrive. About how many more people are expected to arrive? Use compatible numbers. Show your work.<\/p>\n

    Answer:<\/p>\n

    Given,<\/p>\n

    A theater sells tickets = 408<\/p>\n

    People arrive to theater = 253<\/p>\n

    Expected people to arrive = 408 – 253 = 155<\/p>\n

    The compatible numbers for 408 and 253 is 410 and 250<\/p>\n

    410\u00a0 – 250 = 150<\/p>\n

    Do You Know How?<\/strong><\/p>\n

    In 3-6, estimate. Use rounding or compatible numbers. Tell how you made each estimate.<\/p>\n

    Question 3.
    \n321 \u2013 182
    \nAnswer:<\/p>\n

    Compatible numbers are pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

    The compatible numbers for 321 and 182 is 320 and 180.
    \n\"Envision<\/p>\n

    Question 4.
    \n655 \u2013 189
    \nAnswer:<\/p>\n

    Compatible numbers are pair of numbers that are easy to add, subtract, multiply or division mentally.<\/p>\n

    The compatible numbers for 655 and 189 is 660 and 190
    \n\"Envision<\/p>\n

    Question 5.
    \n763 \u2013 471
    \nAnswer:<\/p>\n

    Compatible numbers are pair of numbers that are easy to add, subtract multiply, and division mentally.<\/p>\n

    The compatible numbers for 763 and 471 are 760 and 470.
    \n\"Envision<\/p>\n

    Question 6.
    \n816 \u2013 297
    \nAnswer:<\/p>\n

    Compatible numbers are pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

    The compatible numbers for 816 and 297 are 820 and 300.
    \n\"Envision<\/p>\n

    Independent Practice<\/strong><\/p>\n

    In 7-10, round to the nearest hundred to estimate.<\/p>\n

    Question 7.
    \n286 \u2013 189
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred look at the ten’s place.The ten’s place of 286 is 8 now round to the next hundred.
    \n286 round to the nearest hundred to estimate is 300.<\/p>\n

    The ten’s place of the number 189 is 8 now round to the next hundred
    \n189 round to the nearest hundred to estimate is 200.
    \n300 – 200 = 100<\/p>\n

    Question 8.
    \n461 \u2013 216<\/p>\n

    Answer:<\/p>\n

    When rounding to the nearest hundred look at the ten’s place.The ten’s place of the number 461 is 6 now round to the next hundred.<\/p>\n

    461 round to the nearest hundred to estimate is 500.<\/p>\n

    The ten’s place of the number 216 is 1 now round to the\u00a0 previous hundred.
    \n216 round to the nearest hundred to estimate is 200.
    \n500 – 200 = 300<\/p>\n

    Question 9.
    \n891 \u2013 686
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred look at the ten’s place of the number 891 is 9 now round to the next hundred.
    \n891 round to the nearest hundred to estimate is 900.<\/p>\n

    The ten’s place of the number 686 is 8 now round to the next hundred.
    \n686 round to the nearest hundred to estimate is 700.
    \n900 – 700 = 200<\/p>\n

    Question 10.
    \n724 \u2013 175
    \nAnswer:<\/p>\n

    When rounding to the nearest hundred look at the ten’s place of the number 724 is 2 now round to the previous hundred.
    \n724 round to the nearest hundred to estimate is 600.<\/p>\n

    The ten’s place of the number 175 is 7 now round to the next hundred.
    \n175 round to the nearest hundred to estimate is 200
    \n600 – 200 = 400<\/p>\n

    In 11-14, round to the nearest ten to estimate.<\/p>\n

    Question 11.
    \n766 \u2013 492
    \nAnswer:<\/p>\n

    Here the digit of the one’s place of the number 766 is 6 now round to the nearest ten which is greater than the number.
    \n766 round to the nearest ten to estimate is 770.<\/p>\n

    The one’s place of the number 492 is 2 now round to the nearest ten which is less than the number.
    \n492 round to the nearest ten to estimate is 500.
    \n770 – 500 = 270<\/p>\n

    Question 12.
    \n649 \u2013 487
    \nAnswer:<\/p>\n

    Here the digit of the one’s place of the number 649 is 9 now round to the nearest hundred which is greater than the number.
    \n649 round to the nearest ten to estimate is 650.<\/p>\n

    The one’s place of the number 487 is 7 now round to the nearest hundred which is greater than the number.
    \n487 round to the nearest ten to estimate is 490.
    \n650 – 490 = 169<\/p>\n

    Question 13.
    \n241 \u2013 117
    \nAnswer:<\/p>\n

    Here the digit in the one’s place of the number 241 is 1 now round to the nearest hundred which is less than the number.
    \n241 round to the nearest ten to estimate is 240.<\/p>\n

    The one’s place of the number 117 is 7 now round to the nearest hundred which is greater than the number.
    \n117 round to the nearest ten to estimate is 120.
    \n240 – 120 = 120<\/p>\n

    Question 14.
    \n994 \u2013 679
    \nAnswer:<\/p>\n

    Here the digit of the one’s place of the number 994 is 4 now round to the nearest hundred which is less than the number.
    \n994 round to the nearest ten to estimate is 1000.<\/p>\n

    The digit in the one’s place of the number 679 is 9 which is greater than the number.
    \n679 round to the nearest ten to estimate is 680.
    \n1000 – 680 = 320<\/p>\n

    In 15-18, use compatible numbers to estimate.<\/p>\n

    Question 15.
    \n760 \u2013 265
    \nAnswer:<\/p>\n

    Compatible numbers are pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

    The compatible numbers for 760 and 265 are 760 and 270.
    \n\"Envision<\/p>\n

    Question 16.
    \n355 \u2013 177
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally<\/p>\n

    Compatible numbers for 355 and 177 is 360 and 180.
    \n\"Envision<\/p>\n

    Question 17.
    \n481 \u2013 105
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

    The compatible numbers for 481 and 105 is 480 and 110.<\/p>\n

    \"Envision<\/p>\n

    Question 18.
    \n794 \u2013 556
    \nAnswer:<\/p>\n

    Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

    The compatible numbers for 794 and 556 are 800 and 560.
    \n\"Envision<\/p>\n

    Problem Solving<\/strong><\/p>\n

    Question 19.
    \nThe Grand Concert Hall sold 100 more tickets on Sunday than on Friday. On what day did it sell about 150 tickets more than it sold on Sunday?<\/p>\n

    Use estimation strategies to help find your answers.
    \n\"Envision<\/p>\n

    Question 20.
    \nModel with Math<\/strong> Find the total number of tickets sold on Thursday and Friday. Explain what math you used.
    \nAnswer:
    \nNumber of tickets sold on Thursday = 323
    \nNumber of tickets sold on Friday = 251
    \nTotal number of tickets sold on Thursday and Friday equal to
    \n321 + 251
    \n300 + 20 + 1 + 200 + 50 +1
    \n500 + 70 + 2
    \n500 + 72 = 572<\/p>\n

    Question 21.
    \nAlgebra<\/strong> Anna and Joe write reports for their science class. Anna’s report is 827 words long. Joe’s report is 679 words long. Round each report length to the nearest ten and estimate how many more words Anna’s report is. Then write an equation that shows exactly how many more words Anna’s report is.
    \nAnswer:
    \nAnna report is 827 long words.
    \nJoe’s report is 679 long words.
    \n827 round to the nearest ten to estimate is 830
    \n679 round to the nearest ten to estimate is 680
    \n830 – 680 = 150
    \nAnna report is 150\u00a0 long words more than Joe’s long report<\/p>\n

    Question 22.
    \nHigher Order Thinking<\/strong> One week Mrs. Runyan earned $486, and the next week she earned $254. If Mrs. Runyan’s goal was to earn $545, by about how much did she exceed her goal? Show how you used estimation to find your answer.
    \nAnswers:
    \nMrs Runyan earned in one week = $486
    \nMrs Runyan earned in next week = $254
    \nTotal she earned in two weeks = $ 486 + $255
    \n=$740
    \nBut she goal to earn is $545
    \nShe exceed her goal = $740 – $545
    \nShe exceed her goal is $ 195<\/p>\n

    Question 23.
    \nAbout how many inches longer was a Brachiosaurus than a Tyrannosaurus rex?
    \n\"Envision
    \nAnswer:
    \nBrachiosaurus length = 972 inches.
    \nTyrannosaurus length = 468 inches.
    \n972 – 468 = 504
    \nBrachiosaurus length is 504 longer than Tyrannosaurus length.<\/p>\n

    Assessment Practice<\/strong><\/p>\n

    Question 24.
    \nEstimate 753 \u2013 221 by rounding each number to the nearest ten.
    \nA. 540
    \nB. 530
    \nC. 520
    \nD. 510
    \nAnswer:
    \n753 round to the nearest ten to estimate is 750.
    \n221 round to the nearest ten to estimate is 220
    \n750 – 220 = 530
    \nThus the correct answer is option B.<\/p>\n

    Question 25.
    \nEstimate 812 \u2013 369 by rounding each number to the nearest hundred.
    \nA. 500
    \nB. 400
    \nC. 300
    \nD. 200
    \nAnswer:
    \n812 round to the nearest hundred to estimate is 810.
    \n369 round to the nearest hundred to estimate is 370.
    \n810 – 370 = 440
    \n440 to the nearest hundred is 400.
    \nThus the correct answer is option B.<\/p>\n

    Lesson 8.8 Model with Math<\/h3>\n

    Activity<\/strong><\/p>\n

    Solve & Share<\/strong><\/p>\n

    A pond has 458 rosy red minnows, 212 white cloud minnows, and 277 goldfish. How many more minnows than goldfish live in the pond?<\/p>\n

    Thinking Habits<\/strong>
    \nBe a good thinker! These questions can help you.
    \n\u2022 How can I use math I know to help solve this problem?
    \n\u2022 How can I use pictures, objects, or an equation to represent the problem?
    \n\u2022 How can I use numbers, words, and symbols to solve the problem?
    \n\"Envision<\/p>\n

    Look Back!<\/strong> Model with Math<\/strong> Explain what math you used to solve this problem.<\/p>\n

    Essential Question<\/strong> How Can You Model With math?<\/p>\n

    A.<\/strong>
    \nDavid has $583 to spend on soccer uniforms. He buys this soccer jersey and 2 soccer shorts. How much money does David spend?<\/p>\n

    What math do I need to use to solve the problem?
    \n\"Envision
    \nI need to show what I know and then choose the needed operations.<\/p>\n

    B.<\/strong> How can I model with math? I can<\/p>\n

      \n
    • apply math I know to solve the problem.<\/li>\n
    • use a bar diagram and equations to represent the problem.<\/li>\n
    • use an unknown to represent the number I am trying to find.<\/li>\n<\/ul>\n

      Here’s my thinking…
      \n\"Envision<\/p>\n

      C.<\/strong>
      \nI will use a bar diagram and an equation.
      \nThe hidden question is: How much does David spend on shorts?
      \n\"Envision
      \n$35 + $35 = ?
      \n$35 + $35 = $70. The shorts cost $70.
      \nSo I need to find the total including the jersey.
      \n\"Envision
      \n$70+ $109 = ?
      \n$70 + $109 = $179. David spends $179.<\/p>\n

      Convince Me! Model with Math<\/strong> How does the bar diagram help you model with math?<\/p>\n

      Guided Practice<\/strong><\/p>\n

      Model with Math<\/strong>
      \nHarris’s office building has 126 windows. Morgan’s bank has 146 windows. Devon’s bank has 110 windows. How many more windows do the banks have altogether than the office building?<\/p>\n

      One way you can model\u00a0 math is by using bar diagrams to represent each step of a two-step problem.
      \n\"Envision<\/p>\n

      Question 1.
      \nWhat is the hidden question you need to answer before you can solve the problem?
      \nAnswer:
      \nHow many windows do the banks have in all?<\/p>\n

      Question 2.
      \n<\/span>Solve the problem. Complete the bar diagrams. Show the equations you used.
      \nAnswer:
      \nMorgan’s bank has 146 windows.
      \nDevon’s bank has 110 windows.
      \nMorgan’s and Devon’s office has 146 + 110 = 256 windows
      \nAnother office windows = 256 -126=130<\/p>\n

      Independent Practice<\/strong><\/p>\n

      Model with Math<\/strong>
      \nRegina’s bakery made 304 pies in January. Her bakery made 34 fewer pies in February. How many pies did her bakery make in both months?<\/p>\n

      Question 3.
      \nWhat is the hidden question you need to answer before you can solve the problem?
      \n\"Envision
      \nAnswer:
      \nHow many pies did the bakery make in February?<\/p>\n

      Question 4.
      \nSolve the problem. Complete the bar diagrams. Show the equations you used.
      \nAnswer:
      \n\"Envision-Math-Common-Core-3rd-Grade-Answer-Key-Topic-8-Use-Strategies-and-Properties-to-Add-and-Subtract-89.8\"
      \n304 – 34 = ?
      \n304 – 34 = 270
      \n304 + 270 = ?
      \n304 + 270 = 574<\/p>\n

      Question 5.
      \nHow would your equations change if the bakery made 34 more pies in February than in January?
      \nAnswer:
      \nI would add 304 + 34 = ? instead of subtracting 304 – 34 = ? to find the number of pies baked in February.<\/p>\n

      Problem Solving<\/strong><\/p>\n

      Performance Task<\/strong><\/p>\n

      Skyscraper Heights<\/strong>
      \nThe Empire State Building in New York is 159 meters taller than the Republic Plaza in Denver. The John Hancock Building in Chicago is 122 meters taller than the Republic Plaza. The Empire State Building is 712 miles away from the Hancock Building. The Hancock Building is 920 miles away from the Republic Plaza. Manuel wants to know how tall the Hancock Building is. Answer Exercises 6-9 to solve the problem.
      \n\"Envision
      \nAnswer:<\/p>\n

      Question 6.
      \nCritique Reasoning<\/strong> Tom said to solve the problem, you should add 159 to the height of the Empire State Building. Do you agree? Explain why or why not.
      \nAnswer:<\/p>\n

      Question 7.
      \nModel with Math<\/strong> What is the hidden question you need to solve in this problem? How can you represent the hidden question?
      \nAnswer:<\/p>\n

      Question 8.
      \nModel with Math<\/strong> Solve the problem. Show the equations you used.
      \nAnswer:<\/p>\n

      Question 9.
      \nUse Appropriate Tools<\/strong> Which tool would you use to represent and explain how to solve the problem: counters, cubes, or place-value blocks? Explain.<\/p>\n

      Model with math<\/strong> means you apply math you have learned to solve problems.
      \n\"Envision
      \nAnswer:<\/p>\n

      Topic 8 Fluency Practice<\/h3>\n

      Activity<\/strong><\/p>\n

      Find a Match<\/strong>
      \nWork 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. Once you find the matches, write the fact families for each of the facts.<\/p>\n

      Clues<\/strong>
      \nA The missing number is 9.<\/p>\n

      B The missing number is 10.<\/p>\n

      C The missing number is 3.<\/p>\n

      D The missing number is 6.<\/p>\n

      E The missing number is 7.<\/p>\n

      F The missing number is 4.<\/p>\n

      G The missing number is 8.<\/p>\n

      H The missing number is 5.<\/p>\n

      \"Envision<\/p>\n

      Answer:
      \n\"Envision-Math-Common-Core-3rd-Grade-Answer-Key-Topic-8-Use-Strategies-and-Properties-to-Add-and-Subtract-90.5\"<\/p>\n

      Topic 8 Vocabulary Review<\/h3>\n

      Glossary<\/strong><\/p>\n

      Understand Vocabulary<\/strong><\/p>\n

      Circle the property of addition shown in the following examples.<\/p>\n

      Word List<\/strong>
      \n\u2022 Associative Property of Addition
      \n\u2022 Commutative Property of Addition
      \n\u2022 compatible numbers
      \n\u2022 estimate
      \n\u2022 Identity Property of Addition
      \n\u2022 inverse operations
      \n\u2022 mental math
      \n\u2022 place value
      \n\u2022 round<\/p>\n

      Question 1.
      \n17 + 14 = 14 + 17
      \nAssociative Property Commutative Property Identity Property
      \nAnswer: Associative property.<\/p>\n

      Question 2.
      \n93 + 0 = 93
      \nAssociative Property Commutative Property Identity Property
      \nAnswer: Identity property.<\/p>\n

      Question 3.
      \n8 + (5 + 9) = (8 + 5) + 9
      \nAssociative Property Commutative Property Identity Property
      \nAnswer: Commutative property.<\/p>\n

      Question 4.
      \n65 + 0 = 0 + 65
      \nAssociative Property Commutative Property Identity Property
      \nAnswer: Identity property.<\/p>\n

      Choose the best term from the box. Write it in the blank.<\/p>\n

      Question 5.
      \nYou ___ when you use the nearest multiple of ten or a hundred.
      \nAnswer: You Estimate sum and differences in the number when you use the nearest multiple of ten or a hundred.<\/p>\n

      Question 6.
      \nAddition and subtraction are ___
      \nAnswer:
      \nAddition and subtraction are the arithmetic operations.<\/p>\n

      Question 7.
      \n___ is the value given to the place a digit has in a number.
      \nAnswer: Place value is the value given to the place a digit has in a number.<\/p>\n

      Question 8.
      \nNumbers that are easy to compute mentally are ___
      \nAnswer: Numbers that are easy to compute mentally are mental math.<\/p>\n

      Question 9.
      \nYou do not need pencil and paper when using ___
      \nAnswer: You do not need pencil and paper when using mental math.<\/p>\n

      Use Vocabulary in Writing<\/strong><\/p>\n

      Question 10.
      \nJim found that 123 + 284 is about 400. Explain what Jim did. Use at least 3 terms from the Word List in your answer.
      \nAnswer: Jim used rounding numbers to add the given numbers.<\/p>\n

      Topic 8 Vocabulary Reteaching<\/h3>\n

      Set A<\/strong>
      \npages 289-292
      \nYou can use properties of addition to help solve addition problems.
      \nThe Commutative Property of Addition
      \n12 + \"Envision = 15 + 12
      \nYou can order addends in any way, and the sum will be the same.
      \n12 + 15 = 15 + 12<\/p>\n

      The Associative Property of Addition
      \n3 + (7 + 8) = (3 + \"Envision) + 8
      \nYou can group addends in any way, and the sum will be the same.
      \n3 + (7 + 8) = (3 + 7) + 8
      \nThe Identity Property of Addition
      \n30 + \"Envision = 30
      \nThe sum of any number and zero is that same number.
      \n30 + 0 = 30<\/p>\n

      Remember<\/strong> that both sides of the equal sign must have the same value.<\/p>\n

      In 1-6, write each missing number.<\/p>\n

      Question 1.
      \n18 + __ = 18
      \nAnswer:
      \n18 + 0 = 18<\/p>\n

      Question 2.
      \n14 + (16 + 15) = (___ +16) + 15
      \nAnswer:
      \n14 + ( 16 + 15) = ( 14 + 16) + 15<\/p>\n

      Question 3.
      \n___ + 13 = 13 + 17
      \nAnswer:
      \n17 + 13 = 13 + 17<\/p>\n

      Question 4.
      \n28 + (__ + 22) = 28 + (22 + 25)
      \nAnswer:
      \n28 + (25 + 22) = 28 + ( 22 + 25 )<\/p>\n

      Question 5.
      \n62 + 21 + 0 = 62 + ___
      \nAnswer:
      \n62 + 21 + 0 = 62 + 21<\/p>\n

      Question 6.
      \n___ + (26 + 78) = (31 + 26) + 78
      \nAnswer:
      \n31 + (26 + 78) = (31 + 26) + 78<\/p>\n

      Question 7.
      \nUse 78 and 34 to write an equation that shows the Commutative Property of Addition.<\/p>\n

      Answer:
      \n78 + 34 = 34 + 78<\/p>\n

      Set B<\/strong>
      \npages 293-296
      \nYou can find patterns using an addition table.
      \n\"Envision
      \nThe green sums increase by 2 down the column and are even numbers.
      \nThe yellow sums increase by 2 down the column and are odd numbers.
      \nUse examples to make generalizations!
      \n\"Envision<\/p>\n

      Remember<\/strong> that properties can help you understand patterns.
      \n\"Envision<\/p>\n

      Question 1.
      \nFind the doubles-plus-2 facts. What pattern do you notice about the sums?
      \nAnswer:<\/p>\n

      Question 2.
      \nExplain why your pattern works.
      \nAnswer:<\/p>\n

      Set C<\/strong>
      \npages 297-300
      \nUse mental math to find 374 + 238.
      \nBreak apart 238: 200 + 30+ 8.
      \nAdd hundreds, tens, and ones.
      \n374 + 200 = 574
      \n574 + 30 = 604
      \n604 + 8 = 612
      \nSo, 374 + 238 = 612.<\/p>\n

      Remember<\/strong> that you can break apart addends when finding sums mentally.<\/p>\n

      Question 1.
      \n302 + 56
      \nAnswer:
      \nUsing mental math
      \n300 + 2 + 50 + 6
      \n300 + 50 + 8
      \n300 + 58 = 358<\/p>\n

      Question 2.
      \n<\/span>463 + 418
      \nAnswer:
      \nUsing mental math
      \n463 + 418
      \n400 + 60 + 3 + 400 + 10 + 8
      \n800 + 70 + 11
      \n800 + 81 = 881<\/p>\n

      Question 3.
      \n222 + 725
      \nAnswer:
      \nUsing mental math
      \n222 + 725
      \n200 + 20 + 2 + 700 + 20 + 5
      \n900 + 40 + 7
      \n900 + 47 = 947<\/p>\n

      Question 4.
      \n689 + 115
      \nAnswer:
      \nUsing mental math
      \n689 + 115
      \n600\u00a0 + 80 + 9 + 100 + 10 + 5
      \n700 + 90 + 14
      \n700 + 104 = 804<\/p>\n

      Set D<\/strong>
      \npages 301-304
      \nThink addition to find 400 \u2013 168.
      \nCount on.
      \n168 + 2 = 170
      \n170 + 30 = 200
      \n200 + 200 = 400
      \n2 +30 + 200 = 232
      \nSo, 400 \u2013 168 = 232.<\/p>\n

      Remember<\/strong> that you can count on when subtracting mentally.<\/p>\n

      Question 1.
      \n523 \u2013 163
      \nAnswer:
      \nUsing mental math
      \n523 – 163
      \n500 + 20 + 3 – 100 + 60 + 3
      \n400 – 40 = 360<\/p>\n

      Question 2.
      \n847 \u2013 372
      \nAnswer:
      \nUsing mental math
      \n847 – 372
      \n800 + 40 + 7 – 300 + 70 + 2
      \n500 – 30 – 5
      \n500 – 25 = 575<\/p>\n

      Question 3.
      \n768 \u2013 259
      \nAnswer:
      \nUsing mental math
      \n768 – 259
      \n700 + 60 + 8 – 200 + 50 + 9
      \n500 + 10 – 1
      \n500 + 9 = 509<\/p>\n

      Question 4.
      \n282 \u2013 125
      \nAnswer:
      \nUsing mental math
      \n282 – 125
      \n200 + 80 + 2 – 100 + 20 + 5
      \n100 + 60 – 3
      \n100 + 57 = 157<\/p>\n

      Set E<\/strong>
      \npages 305-308
      \nYou can use a number line to round.
      \n\"Envision
      \nNearest ten: 437 rounds to 440.
      \n\"Envision
      \nNearest hundred: 437 rounds to 400.
      \nThink about place value when you round.
      \n\"Envision<\/p>\n

      Remember<\/strong> that if a number is halfway between, round to the greater number.<\/p>\n

      Question 1.
      \nRound 374 to the nearest ten and the nearest hundred.
      \nAnswer:
      \n374 round to the nearest ten to estimate is 370.
      \n374 round to the nearest hundred to estimate is 400.<\/p>\n

      Question 2.
      \nRound 848 to the nearest ten and the nearest hundred.
      \nAnswer:
      \n842 round to the nearest ten to estimate is 850.
      \n842 round to the nearest hundred to estimate is 800.<\/p>\n

      Question 3.
      \nMark’s family traveled 565 miles. Rounded to the nearest ten, about how many miles did they travel?
      \nAnswer:
      \nMark’s family traveled 565 miles
      \n565 round to the nearest ten to estimate is 570.
      \nMark’s family traveled 570 miles.
      \nQuestion 4.
      \nSara collected 345 shells. Rounded to the nearest hundred, about how many shells did she collect?
      \nAnswer:<\/p>\n

      Set F<\/strong>
      \npages 309-312<\/p>\n

      Estimate 478 + 112.
      \nRound each addend to the nearest ten.
      \n\"Envision
      \nRound each addend to the nearest hundred.
      \n\"Envision
      \nUse compatible numbers.
      \n\"Envision<\/p>\n

      Remember<\/strong> that compatible numbers are numbers close to the actual numbers and are easier to add mentally.<\/p>\n

      Round to the nearest hundred.<\/p>\n

      Question 1.
      \n367 + 319
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

      Compatible numbers for 367 and 319 is 400 and 300.<\/p>\n

      Question 2.
      \n737 + 127
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally,<\/p>\n

      The compatible numbers for 737 and 127 is 700 and 100<\/p>\n

      Round to the nearest ten.<\/p>\n

      Question 3.
      \n298 + 542
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

      Compatible numbers for 298 and 542 is 300 and 540.<\/p>\n

      Question 4.
      \n459 + 85
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

      The compatible numbers for 459 and 85 is 460 and 90<\/p>\n

      Use compatible numbers.<\/p>\n

      Question 5.
      \n372 + 173
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

      The compatible numbers for 372 and 173 is 370 and 170<\/p>\n

      Question 6.
      \n208 + 164
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

      The compatible numbers for 208 and 164 is 210 and 160<\/p>\n

      Question 7.
      \nWill rounding to the nearest ten or the nearest hundred give a closer estimate of 314 + 247? Explain your answer.
      \nAnswer:
      \n314 + 247 = 561
      \n314 round to the nearest ten to estimate is 310
      \n247 round to the nearest ten to estimate is 250
      \n310\u00a0 +250 = 560<\/p>\n

      Set G<\/strong>
      \npages 313-316
      \nEstimate 486 \u2013 177.
      \nRound each number to the nearest hundred.
      \n\"Envision
      \nRound to the nearest hundred.
      \n\"Envision
      \nUse compatible numbers.
      \n\"Envision<\/p>\n

      Remember<\/strong> that an estimate is close to the actual answer.<\/p>\n

      Question 1.
      \n527 \u2013 341
      \nAnswer:<\/p>\n

      Question 2.
      \n872 \u2013 184
      \nAnswer:<\/p>\n

      Round to the nearest ten.<\/p>\n

      Question 3.
      \n387 \u2013 298
      \nAnswer:<\/p>\n

      Here the digit in the one’s place of the number 387 is 7 now round to the nearest ten which is greater than the number.<\/p>\n

      387 round to the nearest ten is 390<\/p>\n

      The digit in the one’s place of the number 298 is 8 now round to the nearest ten which is greater than the number.<\/p>\n

      287 round to the nearest ten is 290<\/p>\n

      390 – 290 = 100<\/p>\n

      Question 4.
      \n659 \u2013 271
      \nAnswer:<\/p>\n

      Here the digit in the one’s place of the number 659 is 9 now round to the nearest ten which is greater than the number.<\/p>\n

      659 round to the nearest ten is 660<\/p>\n

      The digit in the one’s place of the number 271 is 1 which is less than the number.<\/p>\n

      271 is round to the nearest ten to 270<\/p>\n

      660 – 270 = 390<\/p>\n

      Use compatible numbers.<\/p>\n

      Question 5.
      \n472 \u2013 228
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/p>\n

      The compatible numbers for 472 and 228 is 470 and 230<\/p>\n

      Question 6.
      \n911 – 347
      \nAnswer:<\/p>\n

      Compatible numbers are the pair of numbers that are easy to add, subtract, multiply and division mentally.<\/span><\/p>\n

      Compatible numbers for 911 and 347 is 910 and 350<\/p>\n

      Question 7.
      \nWill rounding to the nearest ten or the nearest hundred give a closer estimate of 848 \u2013 231? Explain your answer.
      \nAnswer:
      \n848 -231 = 617
      \n848 round to the nearest hundred to estimate is 800
      \n231 round to the nearest hundred to estimate is 200
      \n800 – 200 = 600<\/p>\n

      Set H<\/strong>
      \npages 317-320
      \nThink about these questions to help you model with math<\/strong>.<\/p>\n

      Thinking Habits<\/strong>
      \n\u2022 How can I use math I know to help solve this problem?
      \n\u2022 How can I use pictures, objects, or an equation to represent the problem?
      \n\u2022 How can I use numbers, words, and symbols to solve the problem?
      \n\"Envision<\/p>\n

      Remember<\/strong> to apply the math you know to solve problems.
      \nElena has $265. She buys a jacket that costs $107 and a sweater that costs $69. How much money does Elena have left?<\/p>\n

      Question 1.
      \nWhat is the hidden question you need to answer before you can solve the problem?
      \nAnswer:<\/p>\n

      Question 2.
      \nSolve the problem. Draw bar diagrams to represent the problem. Show the equations you used.
      \nAnswer:<\/p>\n

      Toni read 131 pages on Monday, 56 pages on Tuesday, and some pages on Wednesday. She read 289 pages in all. How many pages did Toni read on Wednesday?<\/p>\n

      Ans:<\/p>\n

      Toni read pages on Monday = 131<\/p>\n

      Toni read pages on Tuesday = 56<\/p>\n

      Toni read pages on Wednesday = 289 – 131 + 56 = 102<\/p>\n

      Question 1.
      \nWhat is the hidden question you need to answer before you can solve the problem?
      \nAnswer:<\/p>\n

      Question 2.
      \nSolve the problem. Use equations to represent your work.
      \nAnswer:<\/p>\n

      Topic 8 Assessment Practice<\/h3>\n

      Question 1.
      \nWhat is the sum of 243, 132, and 157?
      \nAnswer:
      \n243 + 132 + 157 = 532<\/p>\n

      Question 2.
      \nFind a reasonable estimate for the sum of 171 and 69. Select all that apply.
      \n\"Envision 175 + 70 = 245
      \n\"Envision 100 + 60 = 160
      \n\"Envision 170 + 70 = 240
      \n\"Envision 175 + 75 = 250
      \n\"Envision 130 + 70 = 200
      \nAnswer:<\/p>\n

      For the sum of 171 and 69 is we will appy 175 + 70 = 245 in the equation we are using the\u00a0 compatible numbers<\/p>\n

      170 + 70 = 240 in this equation we are using the nearest ten.<\/p>\n

      Question 3.
      \nSubtract 382 \u2013 148 mentally. Which of the following should you do first to find the difference?
      \nA. Add 2 to 148 and add 2 to 382.
      \nB. Add 2 to 148 and subtract 2 from to 382.
      \nC. Subtract 8 from 148 and subtract 2 from 382.
      \nD. Subtract 12 from 382 and add 12 to 148.
      \nAnswer:
      \nTo find the difference first to subtract 12 from 382 and add 12 to 148.<\/p>\n

      Question 4.
      \nEstimate the difference of 765 and 333. Explain your estimate.
      \nAnswer:
      \nThe difference of 765 and 333 is
      \n765 – 333 = 432
      \nOur estimate is to Subtract the lowest value from the highest value.<\/p>\n

      Question 5.
      \nLook at the sums in the shaded column. Look at the addends. What pattern do you see? Explain why this pattern is always true.
      \n\"Envision
      \nAnswer:<\/p>\n

      Question 6.
      \nUse mental math to add 332 and 154. Which of these shows how to break apart the numbers into hundreds, tens, and ones?
      \nA. Break 332 into 320 + 12. Break 154 into 125 + 29.
      \nB. Break 332 into 100+ 230 + 2. Break 154 into 100 + 52 + 2.
      \nC. Break 332 into 300 + 16 + 16. Break 154 into 100 + 27 + 27.
      \nD. Break 332 into 300 + 30+ 2. Break 154 into 100 + 50 + 4.
      \nAnswer:
      \nD is the correct answer .<\/p>\n

      Question 7.
      \nUse mental math to find 634 \u2013 528.
      \nAnswer:
      \n634 – 528
      \n600 + 30 + 4 – 500 + 20 + 8
      \n100 +10 – 4
      \n110 – 4 = 106<\/p>\n

      Question 8.
      \nSelect all the equations that are true.
      \n\"Envision 32 + 56 + 10 = 10 + 56 + 32
      \n\"Envision (49 + 28) + 5 = 49 + (28 + 5)
      \n\"Envision 56 + 890 = 890 + 56
      \n\"Envision 82 + 0 = 82
      \n\"Envision 45+ 27 = 27 + 35
      \nAnswer:<\/p>\n

      Yes all the equations are true they are in the associative property, commutative property and identity property.<\/p>\n

      Question 9.
      \nLook at the table.
      \n\"Envision
      \nWrite the letters A, B, C, and D above the number line to show each number rounded to the nearest ten.
      \n\"Envision
      \nAnswer:<\/p>\n

      Question 10.
      \nUse the subtraction work shown.
      \n\"Envision
      \nWhich strategy shows a way to check the work using inverse operations?
      \nA. Subtract 57 from 169.
      \nB. Add 57 and 112.
      \nC. Add 112 and 169.
      \nD. Add 169 and 57.
      \nAnswer:
      \nInverse means reverse operation
      \nInverse operation is the Add 169 and 57<\/p>\n

      Question 11.
      \nEstimate the sum of 405 and 385 by rounding to the nearest hundred. Explain your estimate.
      \nAnswer:
      \nThe sum of 405 + 385 = 790<\/p>\n

      When rounding to the nearest hundred look at the ten’s place of the number. The ten’s place of the 790 is 9 now round to the next hundred.
      \n790 round to the nearest hundred to estimate is 800.<\/p>\n

      Question 12.
      \nWhat addition equation can be used to check the answer for 456 \u2013 342 = 114? Draw a bar diagram to show how the numbers in this problem are related.
      \nAnswer:
      \n\"Envision<\/p>\n

      Question 13.
      \nFind the sum of 350, 62, and 199.
      \nA. Draw a bar diagram that represents the problem.
      \nB. What is the first step you would do to solve this problem using mental math?
      \nAnswer:
      \n\"Envision
      \nThe sum of 350 + 62 + 199 = 611<\/p>\n

      Question 14.
      \nSubtract 341 – 97 mentally. First add 3 to 97 to get 100. What should the next step be? What is the difference?
      \nA. Add 6 to 341. The difference is 247.
      \nB. Add 200 to 100. The difference is 100.
      \nC. Subtract 3 from 341. The difference is 238.
      \nD. Add 3 to 341. The difference is 244.
      \nAnswer: The next step is Subtract 3 from 341. The difference is 238.<\/p>\n

      Question 15.
      \nRound each number on the left to the nearest hundred. Select the appropriate answer.
      \n\"Envision
      \nAnswer
      \n668 round to the nearest hundred to estimate is 700.
      \n404 round to the nearest hundred to estimate is 400.
      \n649 round to the nearest hundred to estimate is 600.
      \n489 round to the nearest hundred to estimate is 500.<\/p>\n

      Question 16.
      \nExplain how to use mental math to find 620 – 278.
      \nAnswer:
      \nUsing the mental math
      \n620 – 278
      \n600 + 20 – 200 + 70 + 8
      \n600 + 20 – 200 + 78
      \n600 + 20 – 278
      \n620 – 278 = 332<\/p>\n

      Question 17.
      \nHow can you check the answer for 693 \u2013 231 = 462?
      \nA. Subtract 639 \u2013 300 = 339.
      \nB. Subtract 462 \u2013 231 = 231.
      \nC. Add 693 + 231 = 924.
      \nD. Add 462 + 231 = 693.
      \nAnswer:
      \nThe correct answer is D.
      \n693 – 231 = 462
      \n462 + 231 = 693
      \nQuestion 18.
      \nConsider the sum of 123, 201, and 387.
      \nA. Estimate the sum by rounding to the nearest ten. Explain your estimate.
      \nB. What is the difference between the exact sum of 123, 201, and 387 and your estimate? Explain your answer.
      \nAnswer:
      \nThe sum of 123 + 201 + 387 = 711
      \nA. 711 round to the nearest ten to estimate is 710
      \nB. The difference between the exact sum and the estimate sum is 711 – 710 is 1.<\/p>\n

      Question 19.
      \nConsider the equation 360 = __ + 84.
      \nUse a bar diagram to represent the equation. Then solve for the unknown value.
      \nAnswer:
      \n360 = 276 + 84
      \n\"Envision<\/p>\n

      Topic 8 Performance Task<\/h3>\n

      Vacation Trip<\/strong>
      \nMia is planning a vacation in Orlando, FL.
      \nThe Mia’s Route table shows her route and the miles she will drive.<\/p>\n

      Use the Mia’s Route table to answer Questions 1-3.<\/p>\n

      Question 1.
      \nRound each distance to the nearest ten to show about how many miles Mia will drive on each part of her trip.
      \n\"Envision
      \nMemphis, TN, to Birmingham, AL:<\/p>\n

      Birmingham, AL, to Gainesville, FL:<\/p>\n

      Gainesville, FL, to Orlando, FL:
      \nAnswer:
      \nMia’s drive from Memphis,TN, to Birmingham, AL is 237 miles.
      \n237 is round to the nearest ten is to estimate is 240.
      \nMia’s drives from Memphis, TN, to Birmingham, AL is 240 miles.
      \nMia’s drive from Birmingham, AL to Gainesville, FL is 422
      \n422 round to the nearest ten to estimate is 420
      \nMia’s drive from Birmingham, AL to Gainesville, FL is 420 miles.
      \nMia’s drive from Gainesville, FL to Orlando, FL is 183 miles.
      \n183 round to the nearest ten to estimate is 180.
      \nMia’s drive from Gainesville, FL to Orlando, FL is 180 miles.<\/p>\n

      Question 2.
      \nUse mental math to find the actual number of miles Mia will drive to reach Gainesville. Show your work.
      \nAnswer:
      \nMia’s started a drive from Memphis, TN to Birmingham, AL is 237 miles.
      \nFrom Birmingham, AL to Gainesville, FL is 422 miles.
      \nMia’s drive to reach Gainesville is 237 + 422
      \nBy using mental math
      \n237 +422
      \n200 + 30 + 7 + 400 + 20 + 2
      \n600 + 50 + 9
      \n600 + 59 = 659<\/p>\n

      Question 3.
      \n<\/span>Mia says, \u201cBirmingham is 185 miles closer to Memphis than to Gainesville.\u201d Her brother says, \u201cNo, it is 175 miles closer.” Use mental math to decide who is correct. Show your work.
      \nAnswer:
      \nBirmingham\u00a0 to Memphis is 237 miles.
      \nBirmingham to Gainesville is 422 miles.
      \nMia’s says the correct
      \n422 – 237
      \n400 + 20 + 2 – 200 + 30 + 7
      \n200 – 10 – 5
      \n200 – 15 = 185<\/p>\n

      Mia has to book a hotel and buy theme park tickets. The Hotel Prices and Theme Park Prices tables show the total prices for Mia’s stay. The Mia’s Options list shows two plans that Mia can choose from.<\/span><\/p>\n

      \"Envision<\/p>\n

      Question 4.
      \nMia has $600 to spend on a hotel and tickets.
      \nPart A<\/strong>
      \n\"Envision
      \nWhich option does Mia have enough money for? Explain using estimation.
      \nPart B<\/strong>
      \nCreate a new option for Mia. Fill out the table with a hotel and a theme park. Explain why Mia has enough money for this plan.
      \n\"Envision<\/p>\n

      Question 5.
      \nOne theme park has a special offer. For each ticket Mia buys, she gets another ticket free. Shade the squares in the table at the right to show this pattern. Explain why the pattern is true.
      \n\"Envision
      \nAnswer:<\/p>\n","protected":false},"excerpt":{"rendered":"

      Go through the\u00a0enVision Math Common Core Grade 3 Answer Key\u00a0Topic 8 Use Strategies and Properties to Add and Subtract\u00a0regularly and improve your accuracy in solving questions. enVision Math Common Core 2nd Grade Answers Key Topic 8 Use Strategies and Properties to Add and Subtract Essential Question: How can sums and differences be estimated and found …<\/p>\n","protected":false},"author":1,"featured_media":25590,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/envisionmathanswerkey.com\/wp-content\/uploads\/2021\/06\/enVision-Math-Common-Core-Grade-3-Answer-Key-Topic-8-Use-Strategies-and-Properties-to-Add-and-Subtract.png","_links":{"self":[{"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts\/7800"}],"collection":[{"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/comments?post=7800"}],"version-history":[{"count":4,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts\/7800\/revisions"}],"predecessor-version":[{"id":27953,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts\/7800\/revisions\/27953"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/media\/25590"}],"wp:attachment":[{"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/media?parent=7800"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/categories?post=7800"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/tags?post=7800"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}