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

Answer sheet with worked solutions for the 3rd Grade addition worksheet.

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Success TutoringWorksheetsAnswer sheet3rd Grade · Mathematics · Addition

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

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

1.46 + 48 = 46 + 50 − (answer space) = (answer space)

Answer: 2, 94

  1. 46 + 50 = 96
  2. 96 − 2 = 94
2.157 − 48 = 157 − 50 + (answer space) = (answer space)

Answer: 2, 109

  1. 157 − 50 = 107
  2. I took away 2 too many, so add it back: 107 + 2 = 109
3.154 − 9 = 154 − 4 − (answer space) = (answer space)

Answer: 5, 145

  1. 154 − 4 = 150 (back to a ten)
  2. 150 − 5 = 145
4.41 + 48 = 41 + 50 − (answer space) = (answer space)

Answer: 2, 89

  1. 41 + 50 = 91
  2. 91 − 2 = 89
5.93 − 59 = 93 − 60 + (answer space) = (answer space)

Answer: 1, 34

  1. 93 − 60 = 33
  2. I took away 1 too many, so add it back: 33 + 1 = 34
6.111 − 6 = 111 − 1 − (answer space) = (answer space)

Answer: 5, 105

  1. 111 − 1 = 110 (back to a ten)
  2. 110 − 5 = 105
7.71 + 98 = 71 + 100 − (answer space) = (answer space)

Answer: 2, 169

  1. 71 + 100 = 171
  2. 171 − 2 = 169
8.119 − 29 = 119 − 30 + (answer space) = (answer space)

Answer: 1, 90

  1. 119 − 30 = 89
  2. I took away 1 too many, so add it back: 89 + 1 = 90
9.152 − 5 = 152 − 2 − (answer space) = (answer space)

Answer: 3, 147

  1. 152 − 2 = 150 (back to a ten)
  2. 150 − 3 = 147
10.73 + 48 = 73 + 50 − (answer space) = (answer space)

Answer: 2, 121

  1. 73 + 50 = 123
  2. 123 − 2 = 121
11.120 − 29 = 120 − 30 + (answer space) = (answer space)

Answer: 1, 91

  1. 120 − 30 = 90
  2. I took away 1 too many, so add it back: 90 + 1 = 91
12.32 − 5 = 32 − 2 − (answer space) = (answer space)

Answer: 3, 27

  1. 32 − 2 = 30 (back to a ten)
  2. 30 − 3 = 27
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