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

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

1.75 + 19 = 75 + 20 − (answer space) = (answer space)

Answer: 1, 94

  1. 75 + 20 = 95
  2. 95 − 1 = 94
2.130 − 99 = 130 − 100 + (answer space) = (answer space)

Answer: 1, 31

  1. 130 − 100 = 30
  2. I took away 1 too many, so add it back: 30 + 1 = 31
3.171 − 2 = 171 − 1 − (answer space) = (answer space)

Answer: 1, 169

  1. 171 − 1 = 170 (back to a ten)
  2. 170 − 1 = 169
4.116 + 99 = 116 + 100 − (answer space) = (answer space)

Answer: 1, 215

  1. 116 + 100 = 216
  2. 216 − 1 = 215
5.89 − 19 = 89 − 20 + (answer space) = (answer space)

Answer: 1, 70

  1. 89 − 20 = 69
  2. I took away 1 too many, so add it back: 69 + 1 = 70
6.24 − 5 = 24 − 4 − (answer space) = (answer space)

Answer: 1, 19

  1. 24 − 4 = 20 (back to a ten)
  2. 20 − 1 = 19
7.161 + 48 = 161 + 50 − (answer space) = (answer space)

Answer: 2, 209

  1. 161 + 50 = 211
  2. 211 − 2 = 209
8.83 − 19 = 83 − 20 + (answer space) = (answer space)

Answer: 1, 64

  1. 83 − 20 = 63
  2. I took away 1 too many, so add it back: 63 + 1 = 64
9.33 − 4 = 33 − 3 − (answer space) = (answer space)

Answer: 1, 29

  1. 33 − 3 = 30 (back to a ten)
  2. 30 − 1 = 29
10.58 + 39 = 58 + 40 − (answer space) = (answer space)

Answer: 1, 97

  1. 58 + 40 = 98
  2. 98 − 1 = 97
11.82 − 28 = 82 − 30 + (answer space) = (answer space)

Answer: 2, 54

  1. 82 − 30 = 52
  2. I took away 2 too many, so add it back: 52 + 2 = 54
12.24 − 9 = 24 − 4 − (answer space) = (answer space)

Answer: 5, 15

  1. 24 − 4 = 20 (back to a ten)
  2. 20 − 5 = 15
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