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

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

1.76 + 9 = 76 + 10 − (answer space) = (answer space)

Answer: 1, 85

  1. 76 + 10 = 86
  2. 86 − 1 = 85
2.187 − 98 = 187 − 100 + (answer space) = (answer space)

Answer: 2, 89

  1. 187 − 100 = 87
  2. I took away 2 too many, so add it back: 87 + 2 = 89
3.163 − 9 = 163 − 3 − (answer space) = (answer space)

Answer: 6, 154

  1. 163 − 3 = 160 (back to a ten)
  2. 160 − 6 = 154
4.109 + 18 = 109 + 20 − (answer space) = (answer space)

Answer: 2, 127

  1. 109 + 20 = 129
  2. 129 − 2 = 127
5.123 − 99 = 123 − 100 + (answer space) = (answer space)

Answer: 1, 24

  1. 123 − 100 = 23
  2. I took away 1 too many, so add it back: 23 + 1 = 24
6.192 − 5 = 192 − 2 − (answer space) = (answer space)

Answer: 3, 187

  1. 192 − 2 = 190 (back to a ten)
  2. 190 − 3 = 187
7.83 + 29 = 83 + 30 − (answer space) = (answer space)

Answer: 1, 112

  1. 83 + 30 = 113
  2. 113 − 1 = 112
8.98 − 29 = 98 − 30 + (answer space) = (answer space)

Answer: 1, 69

  1. 98 − 30 = 68
  2. I took away 1 too many, so add it back: 68 + 1 = 69
9.81 − 3 = 81 − 1 − (answer space) = (answer space)

Answer: 2, 78

  1. 81 − 1 = 80 (back to a ten)
  2. 80 − 2 = 78
10.64 + 19 = 64 + 20 − (answer space) = (answer space)

Answer: 1, 83

  1. 64 + 20 = 84
  2. 84 − 1 = 83
11.52 − 18 = 52 − 20 + (answer space) = (answer space)

Answer: 2, 34

  1. 52 − 20 = 32
  2. I took away 2 too many, so add it back: 32 + 2 = 34
12.93 − 6 = 93 − 3 − (answer space) = (answer space)

Answer: 3, 87

  1. 93 − 3 = 90 (back to a ten)
  2. 90 − 3 = 87
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