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2nd Grade Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 4 — Answers

Answer sheet with worked solutions for the 2nd Grade addition worksheet.

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Success TutoringWorksheetsAnswer sheet2nd Grade · Mathematics · Addition

2nd Grade Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 4 — Answers

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

1.66 + 38 = 66 + 40 − (answer space) = (answer space)

Answer: 2, 104

  1. 66 + 40 = 106
  2. 106 − 2 = 104
2.70 − 39 = 70 − 40 + (answer space) = (answer space)

Answer: 1, 31

  1. 70 − 40 = 30
  2. I took away 1 too many, so add it back: 30 + 1 = 31
3.102 − 4 = 102 − 2 − (answer space) = (answer space)

Answer: 2, 98

  1. 102 − 2 = 100 (back to a ten)
  2. 100 − 2 = 98
4.144 + 29 = 144 + 30 − (answer space) = (answer space)

Answer: 1, 173

  1. 144 + 30 = 174
  2. 174 − 1 = 173
5.100 − 39 = 100 − 40 + (answer space) = (answer space)

Answer: 1, 61

  1. 100 − 40 = 60
  2. I took away 1 too many, so add it back: 60 + 1 = 61
6.174 − 6 = 174 − 4 − (answer space) = (answer space)

Answer: 2, 168

  1. 174 − 4 = 170 (back to a ten)
  2. 170 − 2 = 168
7.80 + 39 = 80 + 40 − (answer space) = (answer space)

Answer: 1, 119

  1. 80 + 40 = 120
  2. 120 − 1 = 119
8.74 − 38 = 74 − 40 + (answer space) = (answer space)

Answer: 2, 36

  1. 74 − 40 = 34
  2. I took away 2 too many, so add it back: 34 + 2 = 36
9.193 − 5 = 193 − 3 − (answer space) = (answer space)

Answer: 2, 188

  1. 193 − 3 = 190 (back to a ten)
  2. 190 − 2 = 188
10.163 + 59 = 163 + 60 − (answer space) = (answer space)

Answer: 1, 222

  1. 163 + 60 = 223
  2. 223 − 1 = 222
11.170 − 98 = 170 − 100 + (answer space) = (answer space)

Answer: 2, 72

  1. 170 − 100 = 70
  2. I took away 2 too many, so add it back: 70 + 2 = 72
12.81 − 7 = 81 − 1 − (answer space) = (answer space)

Answer: 6, 74

  1. 81 − 1 = 80 (back to a ten)
  2. 80 − 6 = 74
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