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4th Grade Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 4 — Answers

Answer sheet with worked solutions for the 4th Grade addition worksheet.

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Success TutoringWorksheetsAnswer sheet4th Grade · Mathematics · Addition

4th Grade Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 4 — Answers

Fill in each step of the strategy, then write the answer.

1.107 + 98 = 107 + 100 − (answer space) = (answer space)

Answer: 2, 205

  1. 107 + 100 = 207
  2. 207 − 2 = 205
2.66 − 28 = 66 − 30 + (answer space) = (answer space)

Answer: 2, 38

  1. 66 − 30 = 36
  2. I took away 2 too many, so add it back: 36 + 2 = 38
3.74 − 8 = 74 − 4 − (answer space) = (answer space)

Answer: 4, 66

  1. 74 − 4 = 70 (back to a ten)
  2. 70 − 4 = 66
4.150 + 48 = 150 + 50 − (answer space) = (answer space)

Answer: 2, 198

  1. 150 + 50 = 200
  2. 200 − 2 = 198
5.118 − 39 = 118 − 40 + (answer space) = (answer space)

Answer: 1, 79

  1. 118 − 40 = 78
  2. I took away 1 too many, so add it back: 78 + 1 = 79
6.121 − 2 = 121 − 1 − (answer space) = (answer space)

Answer: 1, 119

  1. 121 − 1 = 120 (back to a ten)
  2. 120 − 1 = 119
7.181 + 59 = 181 + 60 − (answer space) = (answer space)

Answer: 1, 240

  1. 181 + 60 = 241
  2. 241 − 1 = 240
8.130 − 49 = 130 − 50 + (answer space) = (answer space)

Answer: 1, 81

  1. 130 − 50 = 80
  2. I took away 1 too many, so add it back: 80 + 1 = 81
9.194 − 7 = 194 − 4 − (answer space) = (answer space)

Answer: 3, 187

  1. 194 − 4 = 190 (back to a ten)
  2. 190 − 3 = 187
10.34 + 48 = 34 + 50 − (answer space) = (answer space)

Answer: 2, 82

  1. 34 + 50 = 84
  2. 84 − 2 = 82
11.124 − 39 = 124 − 40 + (answer space) = (answer space)

Answer: 1, 85

  1. 124 − 40 = 84
  2. I took away 1 too many, so add it back: 84 + 1 = 85
12.162 − 3 = 162 − 2 − (answer space) = (answer space)

Answer: 1, 159

  1. 162 − 2 = 160 (back to a ten)
  2. 160 − 1 = 159
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