Success TutoringWorksheets

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

Answer sheet with worked solutions for the Year 4 addition worksheet.

Download answers PDFPrint answersBack to worksheet
Success TutoringWorksheetsAnswer sheetYear 4 · Mathematics · Addition

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

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

1.146 + 49 = 146 + 50 − (answer space) = (answer space)

Answer: 1, 195

  1. 146 + 50 = 196
  2. 196 − 1 = 195
2.36 − 9 = 36 − 10 + (answer space) = (answer space)

Answer: 1, 27

  1. 36 − 10 = 26
  2. I took away 1 too many, so add it back: 26 + 1 = 27
3.193 − 8 = 193 − 3 − (answer space) = (answer space)

Answer: 5, 185

  1. 193 − 3 = 190 (back to a ten)
  2. 190 − 5 = 185
4.89 + 9 = 89 + 10 − (answer space) = (answer space)

Answer: 1, 98

  1. 89 + 10 = 99
  2. 99 − 1 = 98
5.75 − 28 = 75 − 30 + (answer space) = (answer space)

Answer: 2, 47

  1. 75 − 30 = 45
  2. I took away 2 too many, so add it back: 45 + 2 = 47
6.122 − 3 = 122 − 2 − (answer space) = (answer space)

Answer: 1, 119

  1. 122 − 2 = 120 (back to a ten)
  2. 120 − 1 = 119
7.142 + 59 = 142 + 60 − (answer space) = (answer space)

Answer: 1, 201

  1. 142 + 60 = 202
  2. 202 − 1 = 201
8.135 − 49 = 135 − 50 + (answer space) = (answer space)

Answer: 1, 86

  1. 135 − 50 = 85
  2. I took away 1 too many, so add it back: 85 + 1 = 86
9.91 − 4 = 91 − 1 − (answer space) = (answer space)

Answer: 3, 87

  1. 91 − 1 = 90 (back to a ten)
  2. 90 − 3 = 87
10.52 + 98 = 52 + 100 − (answer space) = (answer space)

Answer: 2, 150

  1. 52 + 100 = 152
  2. 152 − 2 = 150
11.99 − 38 = 99 − 40 + (answer space) = (answer space)

Answer: 2, 61

  1. 99 − 40 = 59
  2. I took away 2 too many, so add it back: 59 + 2 = 61
12.32 − 8 = 32 − 2 − (answer space) = (answer space)

Answer: 6, 24

  1. 32 − 2 = 30 (back to a ten)
  2. 30 − 6 = 24
Free worksheets at worksheets.successtutoring.com · © Success Tutoring · Free for personal and classroom use

Marking tips

  • Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
  • For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
  • Celebrate what went well first, then pick one thing to work on next.

Great work. Here's what to try next: