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

Answer sheet with worked solutions for the Year 3 addition worksheet.

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Success TutoringWorksheetsAnswer sheetYear 3 · Mathematics · Addition

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

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

1.67 + 39 = 67 + 40 − (answer space) = (answer space)

Answer: 1, 106

  1. 67 + 40 = 107
  2. 107 − 1 = 106
2.31 − 9 = 31 − 10 + (answer space) = (answer space)

Answer: 1, 22

  1. 31 − 10 = 21
  2. I took away 1 too many, so add it back: 21 + 1 = 22
3.44 − 5 = 44 − 4 − (answer space) = (answer space)

Answer: 1, 39

  1. 44 − 4 = 40 (back to a ten)
  2. 40 − 1 = 39
4.53 + 48 = 53 + 50 − (answer space) = (answer space)

Answer: 2, 101

  1. 53 + 50 = 103
  2. 103 − 2 = 101
5.43 − 19 = 43 − 20 + (answer space) = (answer space)

Answer: 1, 24

  1. 43 − 20 = 23
  2. I took away 1 too many, so add it back: 23 + 1 = 24
6.191 − 2 = 191 − 1 − (answer space) = (answer space)

Answer: 1, 189

  1. 191 − 1 = 190 (back to a ten)
  2. 190 − 1 = 189
7.184 + 48 = 184 + 50 − (answer space) = (answer space)

Answer: 2, 232

  1. 184 + 50 = 234
  2. 234 − 2 = 232
8.58 − 29 = 58 − 30 + (answer space) = (answer space)

Answer: 1, 29

  1. 58 − 30 = 28
  2. I took away 1 too many, so add it back: 28 + 1 = 29
9.153 − 9 = 153 − 3 − (answer space) = (answer space)

Answer: 6, 144

  1. 153 − 3 = 150 (back to a ten)
  2. 150 − 6 = 144
10.59 + 48 = 59 + 50 − (answer space) = (answer space)

Answer: 2, 107

  1. 59 + 50 = 109
  2. 109 − 2 = 107
11.131 − 59 = 131 − 60 + (answer space) = (answer space)

Answer: 1, 72

  1. 131 − 60 = 71
  2. I took away 1 too many, so add it back: 71 + 1 = 72
12.192 − 6 = 192 − 2 − (answer space) = (answer space)

Answer: 4, 186

  1. 192 − 2 = 190 (back to a ten)
  2. 190 − 4 = 186
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