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

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

1.80 + 99 = 80 + 100 − (answer space) = (answer space)

Answer: 1, 179

  1. 80 + 100 = 180
  2. 180 − 1 = 179
2.123 − 49 = 123 − 50 + (answer space) = (answer space)

Answer: 1, 74

  1. 123 − 50 = 73
  2. I took away 1 too many, so add it back: 73 + 1 = 74
3.34 − 7 = 34 − 4 − (answer space) = (answer space)

Answer: 3, 27

  1. 34 − 4 = 30 (back to a ten)
  2. 30 − 3 = 27
4.127 + 49 = 127 + 50 − (answer space) = (answer space)

Answer: 1, 176

  1. 127 + 50 = 177
  2. 177 − 1 = 176
5.57 − 38 = 57 − 40 + (answer space) = (answer space)

Answer: 2, 19

  1. 57 − 40 = 17
  2. I took away 2 too many, so add it back: 17 + 2 = 19
6.172 − 3 = 172 − 2 − (answer space) = (answer space)

Answer: 1, 169

  1. 172 − 2 = 170 (back to a ten)
  2. 170 − 1 = 169
7.58 + 48 = 58 + 50 − (answer space) = (answer space)

Answer: 2, 106

  1. 58 + 50 = 108
  2. 108 − 2 = 106
8.137 − 19 = 137 − 20 + (answer space) = (answer space)

Answer: 1, 118

  1. 137 − 20 = 117
  2. I took away 1 too many, so add it back: 117 + 1 = 118
9.24 − 7 = 24 − 4 − (answer space) = (answer space)

Answer: 3, 17

  1. 24 − 4 = 20 (back to a ten)
  2. 20 − 3 = 17
10.158 + 28 = 158 + 30 − (answer space) = (answer space)

Answer: 2, 186

  1. 158 + 30 = 188
  2. 188 − 2 = 186
11.36 − 18 = 36 − 20 + (answer space) = (answer space)

Answer: 2, 18

  1. 36 − 20 = 16
  2. I took away 2 too many, so add it back: 16 + 2 = 18
12.82 − 8 = 82 − 2 − (answer space) = (answer space)

Answer: 6, 74

  1. 82 − 2 = 80 (back to a ten)
  2. 80 − 6 = 74
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