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Year 5 Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 3 — Answers

Answer sheet with worked solutions for the Year 5 addition worksheet.

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Success TutoringWorksheetsAnswer sheetYear 5 · Mathematics · Addition

Year 5 Mental Addition and Subtraction Strategies Worksheet — Level 3 — Practice Set 3 — Answers

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

1.108 + 38 = 108 + 40 − (answer space) = (answer space)

Answer: 2, 146

  1. 108 + 40 = 148
  2. 148 − 2 = 146
2.111 − 49 = 111 − 50 + (answer space) = (answer space)

Answer: 1, 62

  1. 111 − 50 = 61
  2. I took away 1 too many, so add it back: 61 + 1 = 62
3.142 − 4 = 142 − 2 − (answer space) = (answer space)

Answer: 2, 138

  1. 142 − 2 = 140 (back to a ten)
  2. 140 − 2 = 138
4.142 + 48 = 142 + 50 − (answer space) = (answer space)

Answer: 2, 190

  1. 142 + 50 = 192
  2. 192 − 2 = 190
5.117 − 98 = 117 − 100 + (answer space) = (answer space)

Answer: 2, 19

  1. 117 − 100 = 17
  2. I took away 2 too many, so add it back: 17 + 2 = 19
6.192 − 6 = 192 − 2 − (answer space) = (answer space)

Answer: 4, 186

  1. 192 − 2 = 190 (back to a ten)
  2. 190 − 4 = 186
7.104 + 49 = 104 + 50 − (answer space) = (answer space)

Answer: 1, 153

  1. 104 + 50 = 154
  2. 154 − 1 = 153
8.131 − 98 = 131 − 100 + (answer space) = (answer space)

Answer: 2, 33

  1. 131 − 100 = 31
  2. I took away 2 too many, so add it back: 31 + 2 = 33
9.112 − 9 = 112 − 2 − (answer space) = (answer space)

Answer: 7, 103

  1. 112 − 2 = 110 (back to a ten)
  2. 110 − 7 = 103
10.110 + 48 = 110 + 50 − (answer space) = (answer space)

Answer: 2, 158

  1. 110 + 50 = 160
  2. 160 − 2 = 158
11.168 − 98 = 168 − 100 + (answer space) = (answer space)

Answer: 2, 70

  1. 168 − 100 = 68
  2. I took away 2 too many, so add it back: 68 + 2 = 70
12.32 − 4 = 32 − 2 − (answer space) = (answer space)

Answer: 2, 28

  1. 32 − 2 = 30 (back to a ten)
  2. 30 − 2 = 28
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