{"id":13414,"date":"2024-01-01T15:55:04","date_gmt":"2024-01-01T10:25:04","guid":{"rendered":"https:\/\/envisionmathanswerkey.com\/?p=13414"},"modified":"2024-01-02T14:56:29","modified_gmt":"2024-01-02T09:26:29","slug":"envision-math-common-core-grade-2-answer-key-topic-4","status":"publish","type":"post","link":"https:\/\/envisionmathanswerkey.com\/envision-math-common-core-grade-2-answer-key-topic-4\/","title":{"rendered":"enVision Math Common Core Grade 2 Answer Key Topic 4 Fluently Add Within 100"},"content":{"rendered":"

Go through the\u00a0enVision Math Common Core Grade 2 Answer Key<\/a>\u00a0Topic 4 Fluently Add Within 100<\/strong>\u00a0regularly and improve your accuracy in solving questions.<\/p>\n

enVision Math Common Core 2nd Grade Answers Key Topic 4 Fluently Add Within 100<\/h2>\n

Essential Question:<\/strong>
\nWhat are strategies for adding numbers to 100?
\n\"Envision<\/p>\n

enVision STEM Project: Making and Using Models<\/strong>
\nFind Out Find and share books about Hawaii and volcanoes. Make a model of a volcano that becomes an island. Tell about how the island can change over a long time.
\nJournal: Make a Book Show what you learn in a book. In your book, also:<\/p>\n

    \n
  • Draw pictures to show how volcanoes can become islands.<\/li>\n
  • Show how you can use models to help you add numbers to 100.<\/li>\n<\/ul>\n

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

    Vocabulary<\/strong>
    \nQuestion 1.
    \nCircle the tens digit in each number.
    \n73
    \n53
    \n82
    \nAnswer:
    \nThe tens digit in each number is 7,5 and 8.<\/p>\n

    Explanation:
    \nGiven that the digits are 73, 53, 82. So the tens digit in each number is 7,5 and 8.<\/p>\n

    \"Fluently<\/p>\n

    Question 2.
    \nCircle the ones digit in each number.
    \n34
    \n43
    \n97
    \nAnswer:
    \nThe ones digit in each number is 4,3 and 7.<\/p>\n

    Explanation:
    \nGiven that the digits are 73, 53, 82. So the one digit in each number is 4,3 and 7.<\/p>\n

    Question 3.
    \nBreak apart 23 into tens and ones.
    \n23 = _________ tens and ______ ones
    \nAnswer:
    \n23 = 2 tens and 3 ones.<\/p>\n

    Explanation:
    \nGiven that the number is 23, so after a break apart of 23 it will be 2 tens and 3 ones.<\/p>\n

    Mental Math<\/strong>
    \nQuestion 4.
    \nUse mental math to find each sum.
    \n34 + 10 = _________
    \n50 + 5 = _________
    \n20 + 40 = _________
    \nAnswer:
    \n44, 55, 60.<\/p>\n

    Explanation:
    \nThe sum of
    \n34 + 10 = 44
    \n50 + 5 = 55
    \n20 + 40 = 60.<\/p>\n

    Open Number Line<\/strong>
    \nQuestion 5. Use the open number line to find 39 + 15.
    \n\"Envision
    \n39 + 15 = _________
    \nAnswer:<\/p>\n

    Math Story<\/strong>
    \nQuestion 6.
    \nStacy has 17 marbles. Diana gives her 22 marbles. How many marbles does Stacy have now?
    \n______ marbles
    \nAnswer:
    \nThe number of marbles does Stacy has now is 39 marbles.<\/p>\n

    Explanation:
    \nGiven that Stacy has 17 marbles and Diana gives her 22 marbles. So the number of marbles does Stacy has now is 17 + 22 which is 39 marbles.<\/p>\n

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

    PROJECT 4A
    \nWhere can you bike near home?
    \nProject: Make a Bike Trail Brochure
    \n\"Envision<\/p>\n

    PROJECT 4B
    \nWhat kinds of coral grow in Florida?
    \nProject: Build a Coral Model
    \n\"Envision<\/p>\n

    PROJECT 4C
    \nWhat do you collect?
    \nProject: Display a Rock and Leaf Collection
    \n\"Envision<\/p>\n

    PROJECT 4D
    \nHow much does it cost to visit the Kennedy Space Center?
    \nProject: Make a Space Center Poster
    \n\"Envision<\/p>\n

    Lesson 4.1 Add 2-Digit Numbers Using Models<\/h3>\n

    Solve & Share<\/strong>
    \nLeslie collects 36 rocks. Her brother collects 27 rocks. How many rocks do they collect in all? Use place-value blocks to help you solve. Show your place-value blocks.
    \nI can … use models to add 2-digit numbers and then explain my work.
    \n\"Envision<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! When do you need to regroup when adding?<\/p>\n

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

    Add. Use place-value blocks to find each sum. Regroup if needed.
    \nQuestion 1.
    \n32 + 29 = ________
    \n\"Envision
    \n_______ tens ______ ones
    \nAnswer:
    \n6 tens and 1 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 32 + 29 is 61. So there are 6 tens and 1 one.<\/p>\n

    \"Fluently<\/p>\n

    Question 2.
    \n24 + 52 = _______
    \n\"Envision
    \n_______ tens ______ ones
    \nAnswer:
    \n7 tens and 6 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 24 + 52 is 76. So there are 7 tens and 6 ones.<\/p>\n

    Question 3.
    \n15 + 38 = _______
    \n\"Envision
    \n_______ tens ______ ones
    \nAnswer:
    \n5 tens and 3 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 15 + 38 is 53. So there are 5 tens and 3 ones.<\/p>\n

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

    Add. Use place-value blocks to find each sum. Regroup if needed.
    \nQuestion 4.
    \n36 + 29 = _______
    \nAnswer:
    \n6 tens and 5 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 36 + 29 is 65. So there are 6 tens and 5 ones.<\/p>\n

    Question 5.
    \n27 + 23 = _______
    \nAnswer:
    \n5 tens and 0 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 27 + 23 is 50. So there are 5 tens and 0 ones.<\/p>\n

    Question 6.
    \n59 + 13 = _______
    \nAnswer:
    \n7 tens and 2 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 59 + 13 is 72. So there are 7 tens and 2 ones.<\/p>\n

    Question 7.
    \n24 + 35 = _______
    \nAnswer:
    \n5 tens and 9 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 24 + 35 is 59. So there are 5 tens and 9 ones.<\/p>\n

    Question 8.
    \n58 + 25 = _______
    \nAnswer:
    \n8 tens and 3 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 58 + 25 is 83. So there are 8 tens and 3 ones.<\/p>\n

    Question 9.
    \n15+ 46 = _______
    \nAnswer:
    \n6 tens and 1 one.<\/p>\n

    Explanation:
    \nGiven that the sum of 15 + 46 is 61. So there are 6 tens and 1 one.<\/p>\n

    Question 10.
    \n75 + 19 = ________
    \nAnswer:
    \n9 tens and 4 ones.<\/p>\n

    Explanation:
    \nGiven that the sum of 75 + 19 is 94. So there are 9 tens and 4 ones.<\/p>\n

    Question 11.
    \n44 + 47 = _______
    \nAnswer:
    \n9 tens and 1 one.<\/p>\n

    Explanation:
    \nGiven that the sum of 44 + 47 is 91. So there are 9 tens and 1 one.<\/p>\n

    Higher Order Thinking<\/strong> Read the sum. Circle all of the number pairs in the box that match that sum.
    \nQuestion 12.
    \n\"Envision
    \nAnswer:
    \n12 + 10 = 22
    \n18 + 4 = 22.<\/p>\n

    Explanation:
    \nThe number pairs to get the sum as 22 are 12 + 10 and 18 + 4.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-12-1\"<\/p>\n

    Question 13
    \n\"Envision
    \nAnswer:
    \n25 + 30
    \n45 + 10.<\/p>\n

    Explanation:
    \nThe number pairs to get the sum as 55 are 25 + 30 and 45 + 10.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-13-1\"<\/p>\n

    Question 14.
    \n\"Envision
    \nAnswer:
    \n56 + 27
    \n19 + 64.<\/p>\n

    Explanation:
    \nThe number pairs to get the sum as 83 are 56 + 27 and 19 + 64.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-14-1\"<\/p>\n

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

    Solve the problems below. Show your work.
    \nQuestion 15.
    \nModel Chen counts 47 buttons. Then he counts 20 more buttons. How many buttons does Chen count in all?
    \n________ buttons
    \nAnswer:
    \nThe total number of buttons does Chen count in all is 67 buttons.<\/p>\n

    Explanation:
    \nGiven that Chen counts 47 buttons and then he counts 20 more buttons. So the total number of buttons does Chen count in all is 47 + 20 which is 67 buttons.<\/p>\n

    Question 16.
    \nen Vision\u00ae STEM There were 24 earthquakes in the U.S. one year. There were 28 earthquakes the next year. How many earthquakes were there in those two years?
    \n________ earthquakes
    \nAnswer:
    \nThe number of earthquakes in those two years is 52 earthquakes.<\/p>\n

    Explanation:
    \nGiven that there were 24 earthquakes in the U.S in one year and in other year there were 28 earthquakes the next year. So the number of earthquakes is 24 + 28 which is 52 earthquakes.<\/p>\n

    Question 17.
    \nHigher Order Thinking<\/strong> Write an addition story about the desks and chairs in your classroom. Use pictures, numbers, or words.
    \nAnswer:<\/p>\n

    Question 18.
    \nAssessment Practice<\/strong> Do you have to regroup to find each sum? Choose Yes or No.
    \n\"Envision
    \nAnswer:<\/p>\n

    Lesson 4.2 Continue to Add 2-Digit Numbers Using Models<\/h3>\n

    Solve & Share<\/strong>
    \nWendy picked 35 pears. Toni picked 49 pears. How many pears did they pick in all? Use place-value blocks to help explain your work.
    \nI can … add numbers using place value and properties of operations.
    \n\"Envision<\/p>\n

    Answer:
    \nThe total number of pears that they picked up is 84 pears.<\/p>\n

    Explanation:
    \nGiven that Wendy picked 35 pears andToni picked 49 pears. So the total number of pears that they picked up is 35 + 49 which is 84 pears.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-16-1\"<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! Ken adds 43 + 27. His sum is 60. Is he correct? Explain.<\/p>\n

    Answer:
    \nNo, Ken is not correct.<\/p>\n

    Explanation:
    \nNo, Ken is not correct, because 43 + 27 is 70 but he got the sum as 60.<\/p>\n

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

    Add. Use place value. Draw blocks or use another way.
    \nQuestion 1.
    \n12 + 23 = ________
    \n\"Envision<\/p>\n

    Answer:
    \nThe sum of 12 + 23 is 35.<\/p>\n

    Explanation:
    \nThe sum of
    \n12
    \n+23
    \n——
    \n30
    \n5
    \n——
    \n35<\/p>\n

    Question 2.
    \n18 + 42 = _______
    \n\"Envision
    \nAnswer:
    \nThe sum of 18 + 42 is 60.<\/p>\n

    Question 3.
    \n33 + 48 = ________
    \nAnswer:
    \nThe sum of 33 +48 is 81<\/p>\n

    Explanation:
    \nThe sum of
    \n33
    \n+48
    \n——
    \n70
    \n11
    \n——
    \n81<\/p>\n

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

    Add. Use place value. Draw blocks or use another way.
    \nQuestion 4.
    \n18 + 24 = ________
    \nAnswer:
    \nThe sum of 18 + 24 is 42<\/p>\n

    Explanation:
    \nThe sum of
    \n18
    \n+24
    \n——
    \n30
    \n12
    \n——
    \n42<\/p>\n

    Question 5.
    \n47 + 38 = ________
    \nAnswer:
    \nThe sum of 47 + 38 is 85<\/p>\n

    Explanation:
    \nThe sum of
    \n47
    \n+38
    \n——
    \n70
    \n15
    \n——
    \n85<\/p>\n

    Question 6.
    \n26 + 47 = ________
    \nAnswer:
    \nThe sum of 26 + 47 is 73<\/p>\n

    Explanation:
    \nThe sum of
    \n26
    \n+47
    \n——
    \n60
    \n13
    \n——
    \n73<\/p>\n

    Question 7.
    \n34 + 58 = ________
    \nAnswer:
    \nThe sum of 34 + 58 is 92<\/p>\n

    Explanation:
    \nThe sum of
    \n34
    \n+58
    \n——
    \n80
    \n12
    \n——
    \n92<\/p>\n

    Question 8.
    \nHigher Order Thinking<\/strong> Draw the second addend.
    \n\"Envision
    \nAnswer:<\/p>\n

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

    Solve each problem. Show your work.
    \nQuestion 9.
    \nToby planted 28 trees. Juan planted 36 trees. How many trees did they plant in all?
    \n________ trees
    \nAnswer:
    \nThe number of trees did they plant in all is 64 trees.<\/p>\n

    Explanation:
    \nGiven that Toby planted 28 trees and Juan planted 36 trees. So the number of trees did they plant in all is 28 + 36 which is 64 trees.<\/p>\n

    Question 10.
    \nMake Sense Jenny has 13 tennis balls. Sal had 16 tennis balls, but he gave 7 of them to Joe. How many tennis balls do Jenny and Sal have now?
    \n________ tennis balls
    \nAnswer:
    \nThe number of tennis balls does Jenny and Sal have now is 22 tennis balls.<\/p>\n

    Explanation:
    \nGiven that Jenny has 13 tennis balls and Sal had 16 tennis balls. So the total number of tennis balls is 13 + 16 = 29. He gave 7 of them to Joe, so the number of tennis balls do Jenny and Sal have now is 29 – 7 which is 22 tennis balls.<\/p>\n

    Question 11.
    \nHigher Order Thinking<\/strong> Write an addition story using two 2-digit numbers. Then solve the problem for your story.
    \nAnswer:<\/p>\n

    Question 12.
    \nAssessment Practice<\/strong> which is the same amount as 28 + 16? Choose all that apply.
    \n\"Envision
    \nAnswer:<\/p>\n

    Lesson 4.3 Add with Partial Sums<\/h3>\n

    Solve & Share<\/strong>
    \nMs. Kim’s class has 25 students. Mr. Will’s class has 36 students. Both classes go on a field trip. How many students are on the trip?
    \nDraw place-value blocks to help you solve the problem.
    \nI can … add using place value and partial sums.
    \n___________ students<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! Can you add the ones first and then the tens | when finding 57 + 28 using partial sums? Explain.<\/p>\n

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

    Add. Use partial sums. Draw blocks if you need to.
    \nQuestion 1.
    \n24 + 13
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 37.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 24 and 13. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-23-1\"<\/p>\n

    Question 2.
    \n68 + 7
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 75.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 68 and 7. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-24-1\"<\/p>\n

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

    Add. Use partial sums. Draw blocks if you need to.
    \nQuestion 3.
    \n34 + 25
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 59.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 34 and 25. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-25Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-25Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-25Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-25Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-25-1\"<\/p>\n

    Question 4.
    \n68 + 18
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 86.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 68 and 18. Now we will perform a partial sum of those numbers,<\/p>\n

    Question 5.
    \n37 + 8
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 45.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 37 and 8. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-27-1\"<\/p>\n

    Question 6.
    \n52 + 38
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 90.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 52 and 38. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-28-1Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-28-1Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-28-1Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-28-1Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-28-1\"<\/p>\n

    Question 7.
    \n45 + 29
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 74.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 45 and 29. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-29-1\"<\/p>\n

    Question 8.
    \n28 + 39
    \n\"Envision
    \nAnswer:
    \nThe sum of the given numbers is 67.<\/p>\n

    Explanation:
    \nGiven that the numbers to add is 28 and 39. Now we will perform a partial sum of those numbers,
    \n\"Envision-Math-Common-Core-2nd-Grade-Answer-Key-Topic-4-Fluently-Add-Within-100-30-1\"<\/p>\n

    Number Sense<\/strong> Write each missing tens or ones digit.
    \nQuestion 9.
    \n23 + 1\u2610 = 37
    \nAnswer:
    \n23 + 14 = 37.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n37 – 23\u00a0 = 14.
    \nHere, the missing digit is 4.<\/p>\n

    Question 10.
    \n59 = \u26108 + 31
    \nAnswer:
    \n59 = 28 + 31.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n59 – 31 = 28
    \nHere, the missing digit is 2.<\/p>\n

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

    Solve each problem. Show your work.
    \nQuestion 11.
    \nModel 34 students are on the playground. 17 students are in the gym. How many students are there in all?
    \n_________ students
    \nAnswer:
    \nThe number of students are there in all is 51 students.<\/p>\n

    Explanation:
    \nGiven that 34 students are on the playground and 17 students are in the gym. So the number of students are there in all is 34 + 17 which is 51 students.<\/p>\n

    Question 12.
    \nSarah put 8 white roses in a vase. Then she added 7 red roses and 12 yellow roses to the vase. How many roses are in the vase now?
    \n_______ roses
    \nAnswer:
    \nThe number of roses is in the vase now is 27 roses.<\/p>\n

    Explanation:
    \nGiven that Sarah put 8 white roses in a vase and then she added 7 red roses and 12 yellow roses to the vase. So the number of roses are in the vase now is 8 + 7 + 12 which is 27 roses.<\/p>\n

    \"Envision<\/p>\n

    Question 13.
    \nHigher Order Thinking<\/strong> Write each missing tens or ones digit. What strategy did you use?
    \n12 + 3\u2610 = 50
    \n24 + 3\u2610 = 60
    \n35 + 3\u2610 = 70
    \nAnswer:
    \nThe missing digits are 8, 6, 5.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n50 – 12 = 38.
    \nHere, the missing digit is 8.
    \nTo find the missing digit, we will do subtraction
    \n60 – 24 = 36.
    \nHere, the missing digit is 6.
    \nTo find the missing digit, we will do subtraction
    \n70 – 35 = 35
    \nHere, the missing digit is 5.<\/p>\n

    Question 14.
    \nAssessment Practice<\/strong> which is the sum of 28 + 36? Use partial sums to solve.
    \nA. 8
    \nB. 12
    \nC. 54
    \nD. 64
    \nAnswer:
    \nThe sum of 28 + 36 is 64.<\/p>\n

    Explanation:
    \nThe partial sum of 28 + 36 is
    \n28
    \n+ 36
    \n——————–
    \n20 + 30 = 50
    \n8 + 6\u00a0 \u00a0 \u00a0= 14
    \n——————–
    \n64<\/p>\n

    Lesson 4.4 Add Using Mental Math and Partial Sums<\/h3>\n

    Solve & Share<\/strong>
    \nAdd 46 + 26. Explain how you solved the problem.<\/p>\n

    I can … add numbers using place value and partial sums.<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! Roger found 54 + 27. His sum was 71. Is he correct? Why or why not? Use partial sums to check.<\/p>\n

    Answer:
    \nRoger is not correct.<\/p>\n

    Explanation:
    \nGiven that Roger found 54 + 27. His sum was 71, let’s check using the partial sum
    \n54
    \n+ 27
    \n——————–
    \n50 + 20 = 70
    \n4 + 7\u00a0 \u00a0 \u00a0= 11
    \n——————–
    \n81
    \nRoger is not correct, because the sum of 54 + 27 is 81.<\/p>\n

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

    Write the addition problem. Use partial sums. Add any way you choose. Show your work.
    \nQuestion 1.
    \n34 + 17
    \n\"Envision
    \nAnswer:
    \nThe sum of 34 + 17 is 51.<\/p>\n

    Explanation:
    \nThe partial sum of 34 + 17 is 51.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-1\"<\/p>\n

    Question 2.
    \n52 + 31
    \n\"Envision
    \nAnswer:
    \nThe sum of 52 + 31 is 83.<\/p>\n

    Explanation:
    \nThe partial sum of 52 + 31 is 83.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-2\"<\/p>\n

    Question 3.
    \n35 + 26
    \n\"Envision
    \nAnswer:
    \nThe sum of 35 + 26 is 61.<\/p>\n

    Explanation:
    \nThe partial sum of 35 + 26 is 61.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-3\"<\/p>\n

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

    Write the addition problem. Use partial sums. Add any way you choose. Show your work.
    \nQuestion 4.
    \n15 + 28
    \n\"Envision
    \nAnswer:
    \nThe sum of 15 + 28 is 43.<\/p>\n

    Explanation:
    \nThe partial sum of 15 + 28 is 43.
    \n\"Envision-Math-Common-4Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-4\"<\/p>\n

    Question 5.
    \n29 + 20
    \n\"Envision
    \nAnswer:
    \nThe sum of 29 + 20 is 49.<\/p>\n

    Explanation:
    \nThe partial sum of 29 + 20 is 49.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-5\"<\/p>\n

    Question 6.
    \n63 + 29
    \n\"Envision
    \nAnswer:
    \nThe sum of 63 + 29 is 92.<\/p>\n

    Explanation:
    \nThe partial sum of 63 + 29 is 92.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-6\"<\/p>\n

    Question 7.
    \n37 + 48
    \n\"Envision
    \nAnswer:
    \nThe sum of 37 + 48 is 85.<\/p>\n

    Explanation:
    \nThe partial sum of 37 + 48 is 85.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-7\"<\/p>\n

    Add any way you choose. Show your work.
    \nQuestion 8.
    \n67 + 17 = ________
    \nAnswer:
    \nThe sum of 67 + 17 is 84.<\/p>\n

    Explanation:
    \nThe partial sum of 67 + 17 is 84.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-8\"<\/p>\n

    Question 9.
    \n15 + 18 = ________
    \nAnswer:
    \nThe sum of 15 + 18 is 33.<\/p>\n

    Explanation:
    \nThe partial sum of 15 + 18 is 33.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-9\"<\/p>\n

    Question 10.
    \n43 + 49 = ________
    \nAnswer:
    \nThe sum of 43 + 49 is 92.<\/p>\n

    Explanation:
    \nThe partial sum of 43 + 49 is 92.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-10\"<\/p>\n

    Question 11.
    \n62 + 28 = ________
    \nAnswer:
    \nThe sum of 62 + 28 is 90.<\/p>\n

    Explanation:
    \nThe partial sum of 62 + 28 is 90.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-33-11\"<\/p>\n

    Number Sense<\/strong> Write the missing ones or tens digits.
    \nQuestion 12.
    \n27 + 2\u2610 = 50
    \nAnswer:
    \nThe missing digit is 3.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n50 – 27 = 23.
    \nHere, the missing digit is 3.<\/p>\n

    Question 13.
    \n3\u2610 + 16 = 48
    \nAnswer:
    \nThe missing digit is 2.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n48 – 16 = 32.
    \nHere, the missing digit is 2.<\/p>\n

    Question 14.
    \n\u26104 + 49 = 93
    \nAnswer:
    \nThe missing digit is 4.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n93 – 49 = 44.
    \nHere, the missing digit is 4.<\/p>\n

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

    Solve each problem. Show your work. Use drawings, if needed.
    \nQuestion 15.
    \nAmir plants 25 trees. Juan plants 27 trees. How many trees do they plant in all?
    \n________ trees
    \nAnswer:
    \nThe total number of trees do they plant in all is 52 trees.<\/p>\n

    Explanation:
    \nGiven that Amir plants 25 trees and Juan plant 27 trees, so the total number of trees do they plant in all is 25 + 27 which is 52 trees.<\/p>\n

    Question 16.
    \nOn Monday, Sasha puts 32 pennies in her bank. On Tuesday, she puts 57 more pennies in her bank. How many pennies does she put in her bank on both days?
    \n________ pennies
    \nAnswer:
    \nThe number of pennies does she puts in her bank on both days is 89 pennies.<\/p>\n

    Explanation:
    \nGiven that, on Monday, Sasha puts 32 pennies in her bank, and on Tuesday, she puts 57 more pennies in her bank. So the number of pennies does she puts in her bank on both days is 32 + 57 which is 89 pennies.<\/p>\n

    Question 17.
    \nHigher Order Thinking<\/strong> Write an addition story using 2 two-digit numbers. Then solve the problem for your story.
    \nAnswer:
    \nThe number of toffies is there in all is 86 toffies.<\/p>\n

    Explanation:
    \nThere are 60 toffies in a jar. Harry adds 26 toffies more. How many toffies are there in all?<\/p>\n

    Answer:
    \nGiven that there are 60 toffies in a jar and Harry adds 26 toffies more. So the number of toffies are there in all is 60 +26 which is 86 toffies.<\/p>\n

    Question 18.
    \nAssessment Practice<\/strong> Find 52 + 39 using partial sums. Show how you solved the problem.
    \n52 + 39 = ________
    \nAnswer:
    \nThe sum of 52 + 39 is 91.<\/p>\n

    Explanation:
    \nThe partial sum of 52 + 39 is 91
    \n52
    \n+ 39
    \n——————–
    \n50 + 30 = 80
    \n2 + 9\u00a0 \u00a0 \u00a0= 11
    \n——————–
    \n91<\/p>\n

    Lesson 4.5 Break Apart Numbers and Add Using Mental Math<\/h3>\n

    Solve & Share<\/strong>
    \nMonica has 24 crayons. Paul has 64 crayons. How many crayons do they have in all? Use place-value blocks or draw a picture to explain your work.<\/p>\n

    I can … add within 100 using place value strategies.
    \n\"Envision<\/p>\n

    Answer:
    \nThe number of crayons do they have is 88 crayons.<\/p>\n

    Explanation:
    \nGiven that Monica has 24 crayons and Paul has 64 crayons. So the number of crayons do they have is 64 + 24 which is 88 crayons.<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! Explain one way you can break apart numbers to find 14 + 32.<\/p>\n

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

    Find each sum using mental math. Draw pictures of blocks if needed.
    \nQuestion 1.
    \n\"Envision
    \nAnswer:
    \nThe sum of 17 + 52 is 69.<\/p>\n

    Explanation:
    \nThe sum of 17 + 52 is
    \n17 + (50 + 2)
    \n= (17 + 50) +2
    \n= 67 + 2
    \n= 69.<\/p>\n

    Question 2.
    \n\"Envision
    \nAnswer:
    \nThe sum of 69 + 23 is 92.<\/p>\n

    Explanation:
    \nThe sum of 69 + 23 is
    \n69 + (20 + 3)
    \n= (69 + 20) +3
    \n= 89 + 3
    \n= 92.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-37-1\"<\/p>\n

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

    Find each sum using mental math. Draw pictures of blocks if needed.
    \nQuestion 3.
    \n\"Envision
    \nAnswer:
    \nThe sum of 23 + 26 is 49.<\/p>\n

    Explanation:
    \nThe sum of 23 + 26 is
    \n23 + (20 + 6)
    \n= (23 + 20) +6
    \n= 43 + 6
    \n= 49.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-38-1\"<\/p>\n

    Question 4.
    \n\"Envision
    \nAnswer:
    \nThe sum of 9 + 42 is 51.<\/p>\n

    Explanation:
    \nThe sum of 9 + 42 is
    \n9 + (40 + 2)
    \n= (9 + 40) + 2
    \n= 49 + 2
    \n= 51.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-39-1\"<\/p>\n

    Question 5.
    \n\"Envision
    \nAnswer:
    \nThe sum of 51 + 16 is 67.<\/p>\n

    Explanation:
    \nThe sum of 51 + 16 is
    \n51 + (10 + 6)
    \n= (51 + 10) + 6
    \n= 61 + 6
    \n= 67.
    \n\"Envision-Math-Common-Core-2nd-Grade-Answers-Topic-4-Fluently-Add-Within-100-40-1\"<\/p>\n

    Question 6.
    \n56 + 15 = _______
    \nAnswer:
    \nThe sum of 56 + 15 is 71.<\/p>\n

    Explanation:
    \nThe sum of 56 + 15 is
    \n56 + (10 + 5)
    \n= (56 + 10) + 5
    \n= 66 + 5
    \n= 71.<\/p>\n

    Question 7.
    \n_______ = 76 + 18
    \nAnswer:
    \nThe sum of 76 + 18 is 94.<\/p>\n

    Explanation:
    \nThe sum of 76 + 18 is
    \n76 + (10 + 8)
    \n= (76 + 10) + 8
    \n= 86 + 8
    \n= 94.<\/p>\n

    Question 8.
    \n33 + 49 = ________
    \nAnswer:
    \nThe sum of 33 + 49 is 82.<\/p>\n

    Explanation:
    \nThe sum of 33 + 49 is
    \n33 + (40 + 9)
    \n= (33 + 40) + 9
    \n= 73 + 9
    \n= 82.<\/p>\n

    Add tens and ones to solve.
    \nQuestion 9.
    \nAlgebra One number makes both equations true. Find the missing number.
    \n17 + \u2610 = 28
    \n\u2610 + 28 = 39
    \nAnswer:
    \nThe missing digit is 11.<\/p>\n

    Explanation:
    \nTo find the missing digit, we will do subtraction
    \n28 – 17 = 11.
    \nHere, the missing digit is 11.
    \nTo find the missing digit, we will do subtraction
    \n39 – 28 = 11.
    \nHere, the missing digit is 11.<\/p>\n

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

    Generalize Solve each problem mentally. Show your work. Think about the steps you do every time you break apart numbers to add.
    \nQuestion 10.
    \nBilly puts 34 skateboard wheels in a pile. He puts 34 more wheels in another pile. How many wheels does Billy have in all?
    \n_________ wheels
    \nAnswer:
    \nThe number of wheels does Billy has in all is 68 wheels.<\/p>\n

    Explanation:
    \nGiven that Billy puts 34 skateboard wheels in a pile and he puts 34 more wheels in another pile. So the number of wheels does Billy has in all is 34 + 34 which is 68 wheels.<\/p>\n

    Question 11.
    \nenVision\u00ae STEM A new office and house were built in a town. 24 windows are needed for the office. 18 windows are needed for the house. How many windows are needed in all?
    \n_________ windows
    \nAnswer:
    \nThe number of windows is 42 windows.<\/p>\n

    Explanation:
    \nGiven that a new office and house were built in a town with 24 windows are needed for the office and 18 windows are needed for the house. So the number of windows 24 + 18 which 42 windows.<\/p>\n

    Question 12.
    \nHigher Order Thinking<\/strong> Write a story problem about 14 + 41. Then solve the problem.
    \n14 + 41 = ________
    \nAnswer:<\/p>\n

    Question 13.
    \nAssessment Practice<\/strong> Use mental math to find 15 + 12. Explain why the strategy works.
    \nAnswer:
    \nThe sum of 15 + 12 is 27.<\/p>\n

    Explanation:
    \nThe sum of 15 + 12 is
    \n15 + (10 + 2)
    \n= (15 + 10) + 2
    \n= 25 + 2
    \n= 27.<\/p>\n

    Lesson 4.6 Add More than Two 2-Digit Numbers<\/h3>\n

    Solve & Share<\/strong>
    \n12 + 34 + 28 = ?
    \nTom says he can find the sum by adding 28 and 12 first. He says he can add 34 to that sum to find the total.
    \nDo you agree? Use pictures, words, and numbers to make a math argument. Then solve the problem. Show your work.<\/p>\n

    I can … add three or four 2-digit numbers.
    \n\"Envision<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! Look above. Why do you think the order of the addends changed? Why do you think 24 and 16 were added together?<\/p>\n

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

    Add. Use any strategy. Show your work.
    \nQuestion 1.
    \n18+ 15 + 12 = _______
    \n\"Envision<\/p>\n

    Question 2.
    \n11 + 14 + 39 = ________
    \nAnswer:
    \n11 + 14 + 39 = 64.<\/p>\n

    Explanation:
    \nGiven that 11 + 14 + 39
    \n= 25 + 39
    \n= 64.<\/p>\n

    Question 3.
    \n21 + 14 + 41 + 22 = ________
    \nAnswer:
    \n21 + 14 + 41 + 22 = 98.<\/p>\n

    Explanation:
    \nGiven that 21 + 14 + 41 + 22
    \n= 35 + 63
    \n= 98.<\/p>\n

    Question 4.
    \n21 + 15 + 32 + 25 = ________
    \nAnswer:
    \n21 + 15 + 32 + 25 = 93.<\/p>\n

    Explanation:
    \nGiven that 21 + 15 + 32 + 25
    \n= 36 + 57
    \n= 93.<\/p>\n

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

    Add. Use any strategy. Show your work.
    \nQuestion 5.
    \n27 + 21 + 13 = ________
    \nAnswer:
    \n27 + 21 + 13 = 61.<\/p>\n

    Explanation:
    \nGiven that 27 + 21 + 13
    \n= 48 +13
    \n= 61.<\/p>\n

    Question 6.
    \n16 + 32 + 28 = ________
    \nAnswer:
    \n16 + 32 + 28 = 76.<\/p>\n

    Explanation:
    \nGiven that 16 + 32 + 28
    \n= 48 + 28
    \n= 76.<\/p>\n

    Question 7.
    \n32 + 14 + 42 = ________
    \nAnswer:
    \n32 + 14 + 42 = 88.<\/p>\n

    Explanation:
    \nGiven that 32 + 14 + 42
    \n= 46 + 42
    \n= 88.<\/p>\n

    Question 8.
    \n25 + 17 + 24 + 15 = ________
    \nAnswer:
    \n25 + 17 + 24 + 15 = 81.<\/p>\n

    Explanation:
    \nGiven that 25 + 17 + 24 + 15
    \n= 42 + 39
    \n= 81.<\/p>\n

    Question 9.
    \n32 + 16 + 18 + 31 = ________
    \nAnswer:
    \n32 + 16 + 18 + 31 = 97.<\/p>\n

    Explanation:
    \nGiven that 32 + 16 + 18 + 31
    \n= 48 + 49
    \n= 97.<\/p>\n

    Question 10.
    \n37 + 11 + 13 + 38 = ________
    \nAnswer:
    \n37 + 11 + 13 + 38 = 99.<\/p>\n

    Explanation:
    \nGiven that 37 + 11 + 13 + 38
    \n= 48 + 51
    \n= 99.<\/p>\n

    Algebra<\/strong> Find the missing numbers.
    \nQuestion 11.
    \n8 + 3 + \"Envision + 2 = 18
    \nAnswer:
    \nThe missing digit is 5.<\/p>\n

    Explanation:
    \nLet the missing number be X, 8 + 3 + X + 2 = 18 which is 13 + X = 18.
    \nTo find the missing digit, we will do subtraction
    \nX = 18 – 13
    \n= 5.
    \nHere, the missing digit is 5.<\/p>\n

    Question 12.
    \n5 + \"Envision + 6 + 5 = 19
    \nAnswer:
    \nThe missing digit is 3.<\/p>\n

    Explanation:
    \nLet the missing number be X, 5 + X + 6 + 5 = 19 which is 16 + X = 19.
    \nTo find the missing digit, we will do subtraction
    \nX = 19 – 16
    \n= 3.
    \nHere, the missing digit is 3.<\/p>\n

    Question 13.
    \n7 + 27 + 23 + \"Envision = 61
    \nAnswer:
    \nThe missing digit is 4.<\/p>\n

    Explanation:
    \nLet the missing number be X, 7 + 27 + 23 + X = 61 which is 57 + X = 61.
    \nTo find the missing digit, we will do subtraction
    \nX = 61 – 57
    \n= 4.
    \nHere, the missing digit is 4.<\/p>\n

    Question 14.
    \n\"Envision + 24 + 18+ 4 = 52
    \nAnswer:
    \nThe missing digit is 6.<\/p>\n

    Explanation:
    \nLet the missing number be X, X + 24 + 18 + 4 = 52 which is 46 + X = 52.
    \nTo find the missing digit, we will do subtraction
    \nX = 52 – 46
    \n= 6.
    \nHere, the missing digit is 6.<\/p>\n

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

    Reasoning Solve each problem. Show your work.
    \nQuestion 15.
    \n28 trucks are blue. 32 trucks are yellow. 17 trucks are green. Il trucks are pink. How many trucks are there in all?
    \n\"Envision
    \n_______ trucks
    \nAnswer:
    \nThe total number of trucks is 88 trucks.<\/p>\n

    Explanation:
    \nGiven that there are 28 blue trucks, 32 yellow trucks and 17 green trucks, and 11 pink trucks. So the total number of trucks are 28 + 32 + 17 + 11 which is 88 trucks.<\/p>\n

    Question 16.
    \nJoel won 19 tickets in March, 24 tickets in April, 23 tickets in May, and 16 tickets in June. How many tickets does Joel have in all?
    \n_________ tickets
    \nAnswer:
    \nThe number of tickets Joel has in all is 82 tickets.<\/p>\n

    Explanation:
    \nGiven that Joel won 19 tickets in March, 24 tickets in April, 23 tickets in May, and 16 tickets in June. So the number of tickets Joel have in all is 19 + 24 + 23 + 16 =\u00a0 82 tickets.<\/p>\n

    Question 17.
    \nHigher Order Thinking<\/strong> Henry is adding the numbers 24, 18, and 36. He makes a ten to add. Which ones digits does Henry add first? Explain.
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 18.
    \nAssessment Practice<\/strong> Find the sum. Use any strategy. Show your work.
    \n25 + 16 + 15 + 38 = _________
    \nAnswer:
    \nThe sum of 25 + 16 + 15 + 38 = 94.<\/p>\n

    Explanation:
    \nGiven that 25 + 16 + 15 + 38
    \n= 41 + 53
    \n= 94.<\/p>\n

    Lesson 4.7 Practice Adding Using Strategies<\/h3>\n

    Solve & Share<\/strong>
    \nMaria has 39 stickers. Sally has 28 stickers. They found 14 more stickers. How many stickers do they have in all? Solve. Use any strategy. Explain how you found the answer.
    \nI can … use mental math, strategies, and models to add two, three, or four numbers.
    \n\"Envision<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! Find the sum of 14 + 28 +33 + 22. Explain.<\/p>\n

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

    Add. Use any strategy. Show your work.
    \nQuestion 1.
    \n18 + 43 + 12 = _______
    \n\"Envision
    \nAnswer:<\/p>\n

    Question 2.
    \n29 + 47 = _______
    \nAnswer:
    \nThe sum of 29 + 47 = 76.<\/p>\n

    Explanation:
    \nGiven that 29 + 47 which is
    \n20 + 40 = 60
    \n9 + 7 = 16
    \n60 + 16 = 76.<\/p>\n

    Question 3.
    \n9 + 34 + 21 = _______
    \nAnswer:
    \nThe sum of 9 + 34 + 21 is 64.<\/p>\n

    Explanation:
    \nGiven that 9 + 34 + 21 which is
    \n30 + 20 = 50
    \n9 + 4 + 1 = 14
    \n50 + 14 = 64.<\/p>\n

    Question 4.
    \n33 + 27 + 18 + 13 = _______
    \nAnswer:
    \nThe sum of 33 + 27 + 18 + 13 = 91.<\/p>\n

    Explanation:
    \nGiven that 33 + 27 + 18 + 13 which is
    \n30 + 20 + 10 + 10 = 70
    \n3 + 7 + 8 + 3 = 21
    \n70 + 21 = 91.<\/p>\n

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

    Add. Use any strategy. Show your work.
    \nQuestion 5.
    \n31 + 5 + 29 = _______
    \nAnswer:
    \nThe sum of 31 + 5 + 29 = 65.<\/p>\n

    Explanation:
    \nGiven that 31 + 5 + 29 which is
    \n30 + 20 = 50
    \n1 + 5 + 9 =15
    \n50 + 15 = 65.<\/p>\n

    Question 6.
    \n20 + 18 + 16 = _______
    \nAnswer:
    \nThe sum of 20 + 18 + 16 = 54.<\/p>\n

    Explanation:
    \nGiven that 20 + 18 + 16 which is
    \n20 + 10 + 10 = 40
    \n8 + 6 = 14
    \n40 + 14 = 54.<\/p>\n

    Question 7.
    \n8 + 17 = _______
    \nAnswer:
    \nThe sum of 8 + 17 is 25.<\/p>\n

    Explanation:
    \nGiven that 8 + 17
    \n8 + 7 = 15
    \n10 + 15 = 25.<\/p>\n

    Add. Use partial sums. Think about compatible numbers.
    \nQuestion 8.
    \n\"Envision
    \nAnswer:
    \nThe sum of 25 + 13 + 12 + 5 = 55.<\/p>\n

    Explanation:
    \nGiven that 25 + 13 + 12 + 5 which is
    \n20 + 10 + 10 = 40
    \n5 + 3 + 2 + 5 = 15
    \n40 + 15 = 55.<\/p>\n

    Question 9.
    \n\"Envision
    \nAnswer:
    \nThe sum of 9 + 29 + 5 + 35 = 70.<\/p>\n

    Explanation:
    \nThe sum of 9 + 29 + 5 + 35 which is
    \n20 + 30 = 50
    \n9 + 9 + 5 + 5 = 28
    \n50 + 28 = 78.<\/p>\n

    Question 10.
    \n\"Envision
    \nAnswer:
    \nThe sum of 18 + 24 + 42 + 6 is 90.<\/p>\n

    Explanation:
    \nThe sum of 18 + 24 + 42 + 6 which is
    \n10 + 20 + 40 = 70
    \n8 + 4 + 2 + 6 = 20
    \n70 + 20 = 90.<\/p>\n

    Question 11.
    \n\"Envision
    \nAnswer:
    \nThe sum of 27 + 15 + 33 + 24 = 99.<\/p>\n

    Explanation:
    \nThe sum of 27 + 15 + 33 + 24 is
    \n20 + 10 + 30 + 20 = 80
    \n7 + 5 + 3 + 4 = 19
    \n80 + 19 = 99.<\/p>\n

    Question 12.
    \n\"Envision
    \nAnswer:
    \nThe sum of 13 + 7 + 20 + 55 = 95.<\/p>\n

    Explanation:
    \nThe sum of 13 + 7 + 20 + 55 is
    \n10 + 20 + 50 = 80
    \n3 + 7 + 5 = 15
    \n80 + 15 = 95.<\/p>\n

    Number Sense<\/strong> Solve each problem. In which order did you add the numbers? Explain.
    \nQuestion 13.
    \n22 + 17 + 8 + 3 = ________
    \nAnswer:
    \nThe sum of 22 + 17 + 8 + 3 is 50.<\/p>\n

    Explanation:
    \nThe sum of 22 + 17 + 8 + 3 is
    \n20 + 10 = 30
    \n2 + 7 + 8 + 3 = 20
    \n30 + 20 = 50.<\/p>\n

    Question 14.
    \n5 + 12 + 15 + 3 = ________
    \nAnswer:
    \nThe sum of 5 + 12 + 15 + 3 = 35.<\/p>\n

    Explanation:
    \nThe sum of 5 + 12 + 15 + 3 is
    \n10 + 10 = 20
    \n5 + 2 + 5 + 3 = 15
    \n20 + 15 = 35.<\/p>\n

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

    Solve each problem. Show your work.
    \nQuestion 15.
    \nModel Kim has 38 seashells. Mike has 27 seashells. Use partial sums to find how many shells they have in all. Then check your answer by adding another way.
    \n__________ seashells
    \nAnswer:
    \nThe number of shells they have in all is 65 seashells.<\/p>\n

    Explanation:
    \nGiven that Kim has 38 seashells and Mike has 27 seashells. So the number of shells they have in all is 38 + 27 which is
    \n30 + 20 = 50
    \n8 + 7 = 15.
    \n50 + 15 = 65.<\/p>\n

    Question 16.
    \nen Vision\u00ae STEM Fossils form slowly over millions of years. Many fossils come from the sea. Kyle has 9 fossils, Jorie has 12 fossils, Leah has 6 fossils, and Joshua has 8 fossils. How many fossils do they have in all?
    \n\"Envision
    \n__________ fossils
    \nAnswer:
    \nThe total number of fossils do they have in all is 35 fossils.<\/p>\n

    Explanation:
    \nGiven that Kyle has 9 fossils, Jorie has 12 fossils, Leah has 6 fossils, and Joshua has 8 fossils. So the total number of fossils do they have in all is 9 + 12 + 6 + 8 which is
    \n9 + 6 + 8 + 2 = 25
    \n10 + 25 = 35.<\/p>\n

    Question 17.
    \nHigher Order Thinking<\/strong> Find the sum of 42 + 13 + 18 + 7 = _________ . Explain why your strategy works.
    \nAnswer:
    \nThe sum of 42 + 13 + 18 + 7 is 80.<\/p>\n

    Explanation:
    \nThe sum of 42 + 13 + 18 + 7 is
    \n40 + 10 + 10 = 60
    \n2 + 3 + 8 + 7 = 20
    \n60 + 20 = 80.<\/p>\n

    Question 18.
    \nAssessment Practice<\/strong> Find the sum of 17 + 29 + 46. Use any strategy. Show your work.
    \n17 + 29 + 46 = __________
    \nAnswer:
    \nThe sum of 17 + 29 + 46 = 92.<\/p>\n

    Explanation:
    \nThe sum of 17 + 29 + 46 is
    \n10 + 20 + 40 = 70
    \n7 + 9 + 6 = 22
    \n22 + 70 = 92.<\/p>\n

    Lesson 4.8 Solve One-Step and Two-Step Problems<\/h3>\n

    Solve & Share<\/strong>
    \nThe second graders take a trip to a nature center. The Green Class sees 23 animals. The Blue Class sees 14 animals. The Yellow Class sees 32 animals. How many animals do they see in all?
    \nSolve using drawings, models, or an equation. Be prepared to explain your work.<\/p>\n

    I can … use drawings, models, and equations to solve one- and two-step problems.
    \n\"Envision
    \n_________ animals<\/p>\n

    Answer:
    \nThe total number of animals do they see all is 69 animals.<\/p>\n

    Explanation:
    \nGiven that the second graders take a trip to a nature center. The Green Class sees 23 animals and the Blue Class sees 14 animals and the Yellow Class sees 32 animals. So the total number of animals do they see all is 23 + 14 + 32 which is
    \n= 37 + 32
    \n= 69 animals.<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! What is a different way you can use mental math to find 36 + ? = 53?<\/p>\n

    Answer:
    \n36 + 17 = 53.<\/p>\n

    Explanation:
    \nThe different way we can use mental math is to find 36 + ? = 53 is first we will add 10 to the number 36 then we will get 36 + 10 which is 46 and here the result is 53, so we need to add 7 more. So it will be 46 + 7 which is 53.<\/p>\n

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

    Use the bar diagram and mental math to solve each problem. Then check your work.
    \nQuestion 1.
    \nBruce buys 18 eggs. He uses 10 of them for baking. Then he buys 36 more eggs. How many eggs does Bruce have now?
    \nCheck:
    \n\"Envision
    \n________ eggs
    \nAnswer:
    \nThe total number of eggs is 44 eggs.<\/p>\n

    Explanation:
    \nGiven that Bruce buys 18 eggs and he uses 10 of them for baking, so the number of eggs will be 18 – 10 which is 8 eggs. And then he buys 36 more eggs. So the number of eggs will be 8 + 36 which is 44 eggs.<\/p>\n

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

    Use the bar diagram(s) and mental math to solve each problem. Then check your work.
    \nQuestion 2.
    \nElla has 34 more buttons than Julio. Julio has 49 buttons. How many buttons does Ella have?
    \nCheck
    \n\"Envision
    \n________ buttons
    \nAnswer:
    \nThe number of buttons does Ella has now is 83 buttons.<\/p>\n

    Explanation:
    \nGiven that Ella has 34 more buttons than Julio and Julio has 49 buttons. So the number of buttons does Ella has now is 49 + 34 which is 83 buttons.
    \n\"Envision-Math-Common-Core-Grade-2-Answer-Key-Topic-4-Fluently-Add-Within-100-59-1\"<\/p>\n

    Question 3.
    \n20 students are on the bus. Then 10 students get off the bus. Next, 15 students get on the bus. How many students are on the bus now?
    \nCheck:
    \n\"Envision
    \n________ students
    \nAnswer:
    \nThe total number of students will be 25 students.<\/p>\n

    Explanation:
    \nGiven that there are 20 students are on the bus and then 10 students get off the bus. So the number of students will be 20 – 10 which is 10 students. And then 15 students get on the bus, so the number of students now is 10 + 15\u00a0 which is 25 students. So the total number of students will be 25 students.
    \n\"Envision-Math-Common-Core-Grade-2-Answer-Key-Topic-4-Fluently-Add-Within-100-60-1\"<\/p>\n

    Question 4.
    \nWendy has 14 more crayons than Oscar. Oscar has 54 crayons. How many crayons does Wendy have?
    \n\"Envision
    \n_________ crayons
    \nAnswer:
    \nThe number of crayons Wendy has is 68 crayons.<\/p>\n

    Explanation:
    \nGiven that Wendy has 14 more crayons than Oscar and Oscar has 54 crayons. So the number of crayons Wendy has is 54 + 14 which is 68 crayons.
    \n\"Envision-Math-Common-Core-Grade-2-Answer-Key-Topic-4-Fluently-Add-Within-100-61-1\"<\/p>\n

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

    Solve each problem. Show your work.
    \nQuestion 5.
    \nMake Sense Mariah has 17 figs. Kendra has 20 more figs than Mariah. Toby has 33 more figs than Kendra. How many figs do Kendra and Toby each have?
    \nStep 1:
    \nHow many figs does Kendra have?
    \n________ \"Envision _______ = ________ figs
    \nStep 2: How many figs does Toby have?
    \n________ \"Envision _______ = ________ figs
    \nSolve one step at a time.
    \nAnswer:
    \nKendra has 17 + 20 = 37 figs.
    \nToby has 37 + 33 = 70 figs.<\/p>\n

    Explanation:
    \nGiven that Mariah has 17 figs and Kendra has 20 more figs than Mariah, so the number of figs does Kendra has now is 17 + 20 which is 37 figs.
    \nToby has 33 more figs than Kendra, so the number of figs does Toby has now is 37 + 33 which is 70 figs.<\/p>\n

    Question 6.
    \nHigher Order Thinking<\/strong> 8 girls and some boys are in the pool. In all, 17 children are in the pool. Then some more boys jump in the pool. Now there are 13 boys in the pool. How many more boys jumped in the pool?
    \nStep 1:
    \n________ \"Envision _______ = ________
    \nStep 2:
    \n________ \"Envision _______ = ________
    \n_________ more boys jumped in the pool
    \nAnswer:
    \n4 more boys jumped in the pool.<\/p>\n

    Explanation:
    \nGiven that 8 girls and some boys are in the pool. In all, 17 children are in the pool, so the number of boys in the pool is 17 – 8 which is 9 boys. As some boys jump into the pool and the boys in the pool are 13. So the number of boys who jumped in the pool is 13 – 9 which is 4 boys.<\/p>\n

    Question 7.
    \nAssessment Practice<\/strong> The soccer coach has 18 shirts. She gives 9 of the shirts to some of her players. Then she gets 11 more shirts. How many shirts does the coach have left?
    \nShow how you can solve the problem in two steps.
    \nStep 1:
    \nStep 2:
    \nThe coach has ________ shirts left.
    \nAnswer:
    \nThe coach has 20 shirts left.<\/p>\n

    Explanation:
    \nGiven that the soccer coach has 18 shirts and she gives 9 of the shirts to some of her players, so the number of shirts does coach had is 18 – 9 which is 9 shirts. And then gets 11 more shirts, so the total number of shirts does the coach has left is 9 + 11 which is 20 shirts.<\/p>\n

    Lesson 4.9 Problem Solving<\/h3>\n

    Model with Math<\/strong>
    \nSolve & Share<\/strong>
    \nKim puts 25 toys into an empty toy box. Then she puts 17 more toys in the toy box. How many toys are in the box in all?
    \nUse a model to show the problem. Be ready to explain how your model helps you solve the problem.<\/p>\n

    I can … make models to help solve math problems.
    \n\"Envision<\/p>\n

    Answer:
    \nThe total number of toys in the box is 42 toys.<\/p>\n

    Explanation:
    \nGiven that Kim puts 25 toys into an empty toy box and then she puts 17 more toys in the toy box. So the total number of toys in the box is 25 + 17 which is 42 toys.
    \n\"Envision-Math-Common-Core-Grade-2-Answer-Key-Topic-4-Fluently-Add-Within-100-63-1\"<\/p>\n

    Thinking Habits
    \nCan I write an equation or use a drawing, diagram, table, graph, or objects to show the problem?<\/p>\n

    Visual Learning Bridge
    \n\"Envision<\/p>\n

    Convince Me! How does drawing a bar diagram or writing an equation model a problem? Is there another way to model the problem?<\/p>\n

    Answer:
    \nHere, both the bar diagram and writing an equation model for a problem works.<\/p>\n

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

    Complete the bar diagram. Write an equation to model the problem. Then solve.
    \nQuestion 1.
    \nFlora has 24 books about birds. She has 18 books about bugs. How many books is that?
    \n\"Envision<\/p>\n

    Answer:
    \nThe number of books is 42 books.<\/p>\n

    Explanation:
    \nGiven that Flora has 24 books about birds and she has 18 books about bugs. So the number of books is 24 + 18 which is 42 books.<\/p>\n

    Question 2.
    \nBarb saw 14 cars on Smith Street. She saw 8 cars on Alfred Street. How many more cars did Barb see on Smith Street?
    \n\"Envision
    \n_______ \"Envision _______ = ________ cars
    \nAnswer:
    \nThe number of cars did Barb see on Smith Street is 22 cars.<\/p>\n

    Explanation:
    \nGiven that Barb saw 14 cars on Smith Street and she saw 8 cars on Alfred Street. So the number of cars did Barb see on Smith Street is 14 + 8 which is 22 cars.
    \n\"Envision-Math-Common-Core-Grade-2-Answer-Key-Topic-4-Fluently-Add-Within-100-66-1\"<\/p>\n

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

    Make a model to show each problem. Then use the model to solve. Show your work.
    \nQuestion 3.
    \nAvi takes 16 pictures. Then he takes 17 more pictures. How many pictures does Avi take?
    \n\"Envision
    \nAnswer:
    \nThe number of pictures does Avi take is 33 pictures.<\/p>\n

    Explanation:
    \nGiven that Avi takes 16 pictures and then he takes 17 more pictures. So the number of pictures does Avi take is 16 + 17 which is 33 pictures.<\/p>\n

    Question 4.
    \nTina picks 55 blueberries. Next, Tina eats 6 of these blueberries. Then she picks 27 more. How many blueberries does she have now?
    \nAnswer:
    \nThe number of blueberries does she have now is 76 blueberries.<\/p>\n

    Explanation:
    \nGiven that Tina picks 55 blueberries and Tina eats 6 of these blueberries, so the number of blueberries is 55 – 6 which is 49 blueberries. Now she picks 27 more, so the number of blueberries does she have now is 49 + 27 which is 76 blueberries.<\/p>\n

    Question 5.
    \nRaj finds 47 acorns in his front yard. He finds 29 acorns in his back yard. How many acorns does Raj find in all?
    \nAnswer:
    \nThe number of acorns does Raj finds in all is 76 acorns.<\/p>\n

    Explanation:
    \nGiven that Raj finds 47 acorns in his front yard and he finds 29 acorns in his back yard. So the number of acorns does Raj finds in all is 47 + 29 which is 76 acorns.<\/p>\n

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

    Performance Task
    \nAfrican Safari The Santos family is on an African safari. The chart at the right shows the number of animals they see. How many animals do they see?
    \n\"Envision<\/p>\n

    Question 6.
    \nMake Sense What do you know? What are you asked to find?
    \nAnswer:
    \nHere, we know that how many animals they saw of each type of animal and we need to find the total.<\/p>\n

    Question 7.
    \nModel Make a model to help you find the number of animals they see. Be ready to explain why you chose the model you did.
    \nAnswer:
    \nThe number of animals they see is 51 animals.<\/p>\n

    Explanation:
    \nGiven that there are 15 giraffes, 9 elephants, 16 lions and 11 zebras. So the number of animals they see are 15 + 9 + 16 + 11
    \n= 24 + 27
    \n= 51.<\/p>\n

    Question 8.
    \nModel What other model could you use to show the problem? Make another model. Explain which model you think is better.
    \nAnswer:<\/p>\n

    Topic 4 Fluency Practice Activity<\/h3>\n

    Point & Tally<\/strong>
    \nFind a partner. Get paper and a pencil. Each partner chooses a different color: light blue or dark blue.
    \nPartner I and Partner 2 each point to a black number at the same time. Both partners add those numbers.
    \nIf the answer is on your color, you get a tally mark. Work until one partner gets twelve tally marks.<\/p>\n

    I can … add within 20.
    \n\"Envision<\/p>\n

    Topic 4 Vocabulary Review<\/h3>\n

    Understand Vocabulary
    \nWord List<\/p>\n

      \n
    • addends<\/li>\n
    • compatible numbers<\/li>\n
    • ones<\/li>\n
    • partial sum<\/li>\n
    • regroup<\/li>\n
    • sum<\/li>\n
    • tens<\/li>\n<\/ul>\n

      Use the problem at the right. Write partial sum or sum for each.
      \n\"Envision
      \nQuestion 1.
      \n70 is a _________ .
      \nAnswer:
      \n70 is a partial sum.<\/p>\n

      Explanation:
      \nHere, the number 70 is a partial sum, because partial sum is just a sum of part of sequence.<\/p>\n

      Question 2.
      \n17 is a ___________.
      \nAnswer:
      \n17 is a partial sum.<\/p>\n

      Explanation:
      \nHere, the number 17 is a partial sum, because partial sum is just a sum of part of sequence.<\/p>\n

      Question 3.
      \n87 is the __________.
      \nAnswer:
      \n87 is a sum.<\/p>\n

      Explanation:
      \nHere, the number 87 is a sum, because it is the result of the addition.<\/p>\n

      Question 4.
      \nUse the ones column in the problem at the right. Which compatible numbers can you add to make a ten two different ways?
      \n\"Envision
      \nWrite two different equations.
      \nAnswer:
      \n8 + 2 = 10,
      \n6 + 4 = 10.<\/p>\n

      Explanation:
      \nThe two different equations which are compatible numbers can we add to make a ten is
      \n8 + 2 = 10,
      \n6 + 4 = 10.<\/p>\n

      Use Vocabulary in Writing<\/strong>
      \nQuestion 5.
      \nSolve 27 + 35 by breaking apart both addends. Tell how you solved the problem. Use terms from the Word List.
      \nAnswer:
      \n27 + 35 = 65.<\/p>\n

      Explanation:
      \nHere, we have added the ones and then we will regroup and added to find the sum.
      \n27 + 35 = 65.<\/p>\n

      Topic 4 Reteaching<\/h3>\n

      Set A<\/strong><\/p>\n

      Find 55 + 17. Use place-value blocks. Show the addends. Join the tens and ones. Regroup if needed.
      \n\"Envision<\/p>\n

      Add. Use place-value blocks to show your work. Regroup if needed.
      \nQuestion 1.
      \n36 + 23 = ________
      \n\"Envision<\/p>\n

      Answer:
      \nThe sum of 36 + 23 is 59 which is 5 tens and 9 ones.<\/p>\n

      Explanation:
      \nThe sum of 36 + 23 is
      \n30 + 20 = 50
      \n6 + 3 = 9
      \n50 + 9 = 59.<\/p>\n

      Question 2.
      \n19 + 44 = _______
      \n\"Envision
      \n_______ tens _______ ones
      \nAnswer:
      \nThe sum of 19 + 44 is\u00a0 63 which is 6 tens and 3 ones.<\/p>\n

      Explanation:
      \nThe sum of 19 + 44 is
      \n10 + 40 = 50
      \n9 + 4 = 13
      \n50 + 13 = 63.<\/p>\n

      Set B<\/strong><\/p>\n

      Find 24 + 49. Draw place-value blocks to show the addends. Join the tens and ones. Regroup if needed.
      \n\"Envision<\/p>\n

      Add. Use place value and draw blocks.
      \nQuestion 3.
      \n64 + 13 = _______
      \nAnswer:
      \nThe sum of 64 + 13 is 77 which is 7 tens and 7 ones.<\/p>\n

      Explanation:
      \nThe sum of 64 + 13 is
      \n60 + 10 = 70
      \n4 + 3 = 7
      \n70 + 7 = 77.<\/p>\n

      Question 4.
      \n27 + 56 = ________
      \nAnswer:
      \nThe sum of 23 + 56 is 79 which is 7 tens and 9 ones.<\/p>\n

      Explanation:
      \nThe sum of 23 + 56 is
      \n20 + 50 = 70
      \n3 + 6 = 9
      \n70 + 9 = 79.<\/p>\n

      Set C<\/strong><\/p>\n

      You can draw blocks and use partial sums to find 46 + 37.
      \n\"Envision<\/p>\n

      Add. Draw place-value blocks and use partial sums.
      \nQuestion 5.
      \n33 + 57
      \nDrawings:
      \n\"Envision
      \nAnswer:
      \nThe partial sum of 33 + 57 is 90.<\/p>\n

      Explanation:
      \nGiven that 33 + 57, the partial sum of 33 + 57 is
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-77-1\"<\/p>\n

      Set D<\/strong><\/p>\n

      Find 29 + 63. You can break apart the addends and use partial sums.
      \n\"Envision<\/p>\n

      Add. Break apart the addends and use partial sums.
      \nQuestion 6.
      \n\"Envision
      \nAnswer:
      \nThe partial sum of 17 + 77 is 94.<\/p>\n

      Explanation:
      \nGiven that 17 + 77, the partial sum of 17 + 77 is
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-79-1\"<\/p>\n

      Question 7.
      \n\"Envision
      \nAnswer:
      \nThe partial sum of 24 + 38 is 62.<\/p>\n

      Explanation:
      \nGiven that 24 + 38, the partial sum of 24 + 38 is
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-80-1\"<\/p>\n

      Set E<\/strong><\/p>\n

      Find 32 + 19. Break apart the second addend and add mentally.
      \n\"Envision<\/p>\n

      Break apart the second addend to add. Show your work.
      \nQuestion 8.
      \n\"Envision
      \nAnswer:
      \nThe sum of 24 + 55 is 79.<\/p>\n

      Explanation:
      \nThe sum of 24 + 55 is 79.
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-82-1\"<\/p>\n

      Question 9.
      \n\"Envision
      \nAnswer:
      \nThe sum of 64 + 27 is 91.<\/p>\n

      Explanation:
      \nThe sum of 64 + 27 is 91.
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-83-1\"<\/p>\n

      Set F<\/strong><\/p>\n

      Use partial sums to find 65 + 7 + 13.
      \n\"Envision<\/p>\n

      Add using partial sums.
      \nQuestion 10.
      \n\"Envision
      \nAnswer:
      \nThe partial sum is 70.<\/p>\n

      Explanation:
      \nGiven that 22 + 21 + 9 + 18, the partial sum of 22 + 21 + 9 + 18 is
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-85-1\"<\/p>\n

      Question 11.
      \n\"Envision
      \nAnswer:
      \nThe partial sum of 41 + 15 + 29 + 10 is 95.<\/p>\n

      Explanation:
      \nGiven that 41 + 15 + 29 + 10, the partial sum of 41 + 15 + 29 + 10 is
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-86-1\"<\/p>\n

      Set G<\/strong><\/p>\n

      27 students are eating lunch. More students join them. Now 63 students are eating lunch. How many students joined them?
      \nWrite an equation: 27 + ? = 63 Count on to find the missing addend:
      \n\"Envision
      \nSo, 36 students joined them.<\/p>\n

      Complete the bar diagram, write an equation, and solve.
      \nQuestion 12.
      \nLana has 24 crayons. Then she gets some more crayons. Now she has 42 crayons. How many crayons does Lana get?
      \n\"Envision
      \nAnswer:
      \nThe number of crayons does Lana gets is 66 crayons.<\/p>\n

      Explanation:
      \nGiven that Lana has 24 crayons and then she gets some more crayons and now she has 42 crayons. So the number of crayons does Lana gets is 24 + 42 which is 66 crayons.
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-88-1\"<\/p>\n

      Set H<\/strong><\/p>\n

      Thinking Habits<\/strong>
      \nModel with Math
      \nCan I use a drawing, diagram, table, graph, or objects to show the problem?
      \nCan I write an equation to show the problem?
      \n\"Envision<\/p>\n

      Make a model and solve the problem.
      \nQuestion 13.
      \nStudents ride buses to the museum. 28 students ride in Bus A. 27 students ride in Bus B. How many students ride in both buses?
      \nAnswer:
      \nThe total number of students ride in both buses is 55 students.<\/p>\n

      Explanation:
      \nGiven that 28 students ride in Bus A and 27 students ride in Bus B. So the total number of students ride in both buses is 28 + 27 which is 55 students.<\/p>\n

      Topic 4 Assessment Practice<\/h3>\n

      Question 1.
      \nKelly has 46 beads. Her sister gives her 28 more beads. How many beads does Kelly have now?
      \nA. 18
      \nB. 64
      \nC. 22
      \nD. 74
      \nAnswer:
      \nThe total number of beads does Kelly have now is 74 beads.<\/p>\n

      Explanation:
      \nGiven that Kelly has 46 beads and her sister gives her 28 more beads. So the total number of beads does Kelly have now is 46 + 28 which is 74 beads.<\/p>\n

      Question 2.
      \nWhich are equal to 45 + 38? Choose all that apply.
      \n\u2610 40 + 30 + 5+ 8
      \n\u2610 93
      \n\u2610 45 + 30 + 5 + 3
      \n\u2610 40 + 30 + 10
      \n\u2610 83
      \nAnswer:
      \nOption A and Option E.<\/p>\n

      Explanation:
      \nGiven that 45 + 38, so 45 + 38 is equal to 40 + 30 + 5 + 8 which is 83.<\/p>\n

      Question 3.
      \nIs the sum equal to 81? Choose Yes or No.
      \n\"Envision
      \nAnswer:
      \nOption B and Option D.<\/p>\n

      Explanation:
      \nGiven that the sum equal to 81, so the addends will be 52\u00a0 + 29 and 63 + 18 which is 81.
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-90-1\"<\/p>\n

      Question 4.
      \nFind 27 + 44 using partial sums. Show how you solved the problem.
      \nAnswer:
      \nThe sum of 27 + 44 is 71.<\/p>\n

      Explanation:
      \nThe partial sum of 27 + 44 is
      \n= 27 + 40 + 4
      \n= 67 + 4
      \n= 71.<\/p>\n

      Question 5.
      \nWhich is the sum of 57 + 15?
      \n\"Envision
      \nA. 82
      \nB. 72
      \nC. 62
      \nD. 42
      \nAnswer:
      \nOption B.<\/p>\n

      Explanation:
      \nThe sum of 57 + 15 is 72.<\/p>\n

      Question 6.
      \nWhich are the same amount as 13 + 8 + 7? Choose all that apply.
      \n\u2610 20 + 8
      \n\u2610 10 + 10 + 8
      \n\u2610 18
      \n\u2610 28
      \n\u2610 20 + 7
      \nAnswer:
      \nOption A, Option B and Option D.<\/p>\n

      Explanation:
      \nThe same amount as 13 + 8 + 7 is 20 + 8, 10 + 10 + 8 and 28.<\/p>\n

      Question 7.
      \nWhat is the sum of 26 + 53 + 7? Show your work.
      \n26 + 53 + 7 = ________
      \nAnswer:
      \nThe sum is 86.<\/p>\n

      Explanation:
      \nThe sum of 26 + 53 + 7 is
      \n= 79 + 7
      \n=\u00a0 86.<\/p>\n

      Question 8.
      \nFind the sum of 23 and 19. Then subtract 10 from that sum. Show and explain your work.
      \nThe answer is __________
      \nAnswer:
      \nThe answer is 32.<\/p>\n

      Explanation:
      \nGiven that the sum of 23 and 19 is 42 and should subtract 10 from the sum which is 42 – 10 = 32.<\/p>\n

      Question 9.
      \nA. Find the sum. Use a strategy. Show your work.
      \n25 + 37 + 15 + 8 = __________
      \nAnswer:
      \n25 + 37 + 15 + 8 = 85.<\/p>\n

      Explanation:
      \nThe sum of 25 + 37 + 15 + 8 is
      \n= 25 + 60
      \n= 85.<\/p>\n

      B. Explain how you found the sum and why your strategy works.
      \nAnswer:
      \nHere, we will first add ones and got 25 and then we will regroup the 2 tens and then we will add to get the sum of 85.<\/p>\n

      Question 10.
      \nMs. Wise has 12 tablets. Then she gets 9 more tablets. Ms. Wise has 20 students in her class. She gives each student one tablet. How many tablets does she have left? Use equations to solve the problem.
      \n________ tablet(s)
      \nAnswer:
      \nThe number of tablets left with Ms. Wise is 1 tablet.<\/p>\n

      Explanation:
      \nGiven that Ms. Wise has 12 tablets and she gets 9 more tablets, so the total tablets will be 12 + 9 which is 21 tablets. Ms. Wise has 20 students in her class and she gives each student one tablet. So the number of tablets left with Ms. Wise is 21 – 20 which is 1 tablet.<\/p>\n

      Question 11.
      \nWhat is the sum of 59 + 33?
      \nDraw place-value blocks and show your work in the blue box at the right.
      \n59 + 33 = _________
      \nAnswer:<\/p>\n

      Question 12.
      \nEach equation has a missing addend. Find it in the number cards. Draw lines to match. Then write the missing addend in the gray box.
      \n\"Envision
      \nAnswer:
      \nThe missing addends are 7, 8, 5, 6.<\/p>\n

      Explanation:
      \nGiven that 6 + 14 +– + 3 = 30, so the missing addend is 23 + — = 30 and the missing addend is 30 -23 = 7.
      \nGiven that 3 + 32 + 7 +– = 50, so the missing addend is 42+ — = 50 and the missing addend is 50 – 42= 8.
      \nGiven that 25 + 25\u00a0 +– + 5 = 60, so the missing addend is 55 + — = 60 and the missing addend is 60 – 55 = 5.
      \nGiven that 5 +– + 15 + 14 = 40, so the missing addend is 34 + — = 40 and the missing addend is 40 – 34 = 6.<\/p>\n

      \"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-92-1\"<\/p>\n

      Question 13.
      \nCorey has 17 more marbles than Tony. Tony has 64 marbles. How many marbles does Corey have?
      \n\"Envision
      \nUse the bar diagram to model and solve the problem. Show your work.
      \n_________ marbles
      \nAnswer:
      \nThe total number of marbles is 81 marbles.<\/p>\n

      Explanation:
      \nGiven that Corey has 17 more marbles than Tony and Tony has 64 marbles. So the total number of marbles is 17 + 64 which is 81 marbles.<\/p>\n

      Topic 4 Performance Task<\/h3>\n

      Our Pets
      \nStudents draw pictures of their pets. The chart shows the number of pets the students have.
      \n\"Envision
      \nQuestion 1.
      \nHow many dogs and cats do the students have? Show your work.
      \n_________ dogs and cats
      \nAnswer:
      \n&0 students have dogs and cats.<\/p>\n

      Explanation:
      \nThe total number of dogs and cats is 41 + 29 which is 70 students.<\/p>\n

      Question 2.
      \nHow many cats and fish do the students have? Show your work.
      \n__________ cats and fish
      \nAnswer:
      \n53 students have cats and fish<\/p>\n

      Explanation:
      \nThe total number of cats and fish is 29 + 24 which is 53 students.<\/p>\n

      Question 3.
      \nUse partial sums to find how many cats, rabbits, and fish the students have. Be sure to check your work.
      \n\"Envision
      \nHow many cats, rabbits, and fish in all?
      \n__________ cats, rabbits, and fish
      \nAnswer:
      \n59 students have cats, rabbits, and fish.<\/p>\n

      Explanation:
      \nThe total number of cats, rabbits, and fish is 29 + 6 + 24 which is 59 students.
      \n\"Envision-Math-Common-Core-Grade-2-Answers-Topic-4-Fluently-Add-Within-100-95-1\"<\/p>\n

      Question 4.
      \nExplain how to use partial sums to add.
      \nAnswer:<\/p>\n

      Question 5.
      \nThe students also draw pictures of 10 hamsters, 19 birds, and 5 mice.
      \nPart A
      \nComplete the model to show how to find the total number of hamsters, birds, and mice.
      \n\"Envision
      \nAnswer:<\/p>\n

      Part B
      \nComplete the equation to show how many hamsters, birds, and mice they draw. Then write the total.
      \n\"Envision
      \n__________ hamsters, birds, and mice
      \nAnswer:<\/p>\n","protected":false},"excerpt":{"rendered":"

      Go through the\u00a0enVision Math Common Core Grade 2 Answer Key\u00a0Topic 4 Fluently Add Within 100\u00a0regularly and improve your accuracy in solving questions. enVision Math Common Core 2nd Grade Answers Key Topic 4 Fluently Add Within 100 Essential Question: What are strategies for adding numbers to 100? enVision STEM Project: Making and Using Models Find Out …<\/p>\n","protected":false},"author":1,"featured_media":25624,"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-2-Answer-Key-Topic-4-Fluently-Add-Within-100.png","_links":{"self":[{"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts\/13414"}],"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=13414"}],"version-history":[{"count":4,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts\/13414\/revisions"}],"predecessor-version":[{"id":28204,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/posts\/13414\/revisions\/28204"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/media\/25624"}],"wp:attachment":[{"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/media?parent=13414"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/categories?post=13414"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/envisionmathanswerkey.com\/wp-json\/wp\/v2\/tags?post=13414"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}