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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.

1.23 + 38 = 23 + 40 − (answer space) = (answer space)

Answer: 2, 61

  1. 23 + 40 = 63
  2. 63 − 2 = 61
2.143 − 49 = 143 − 50 + (answer space) = (answer space)

Answer: 1, 94

  1. 143 − 50 = 93
  2. I took away 1 too many, so add it back: 93 + 1 = 94
3.162 − 6 = 162 − 2 − (answer space) = (answer space)

Answer: 4, 156

  1. 162 − 2 = 160 (back to a ten)
  2. 160 − 4 = 156
4.88 + 18 = 88 + 20 − (answer space) = (answer space)

Answer: 2, 106

  1. 88 + 20 = 108
  2. 108 − 2 = 106
5.157 − 49 = 157 − 50 + (answer space) = (answer space)

Answer: 1, 108

  1. 157 − 50 = 107
  2. I took away 1 too many, so add it back: 107 + 1 = 108
6.131 − 9 = 131 − 1 − (answer space) = (answer space)

Answer: 8, 122

  1. 131 − 1 = 130 (back to a ten)
  2. 130 − 8 = 122
7.138 + 48 = 138 + 50 − (answer space) = (answer space)

Answer: 2, 186

  1. 138 + 50 = 188
  2. 188 − 2 = 186
8.127 − 59 = 127 − 60 + (answer space) = (answer space)

Answer: 1, 68

  1. 127 − 60 = 67
  2. I took away 1 too many, so add it back: 67 + 1 = 68
9.52 − 4 = 52 − 2 − (answer space) = (answer space)

Answer: 2, 48

  1. 52 − 2 = 50 (back to a ten)
  2. 50 − 2 = 48
10.109 + 98 = 109 + 100 − (answer space) = (answer space)

Answer: 2, 207

  1. 109 + 100 = 209
  2. 209 − 2 = 207
11.133 − 29 = 133 − 30 + (answer space) = (answer space)

Answer: 1, 104

  1. 133 − 30 = 103
  2. I took away 1 too many, so add it back: 103 + 1 = 104
12.71 − 4 = 71 − 1 − (answer space) = (answer space)

Answer: 3, 67

  1. 71 − 1 = 70 (back to a ten)
  2. 70 − 3 = 67
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