Year 4 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 4 addition worksheet.
Success TutoringWorksheetsAnswer sheetYear 4 · Mathematics · AdditionYear 4 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 3 — Answers
Fill in each step of the strategy, then write the answer.
1.29 + 7 = 29 + 1 + (answer space) = (answer space)
Answer: 6, 36
- 29 + 1 = 30 (a ten)
- 30 + 6 = 36
2.71 + 9 = 71 + 10 − (answer space) = (answer space)
Answer: 1, 80
- 71 + 10 = 81
- 81 − 1 = 80
3.50 + 49 = (answer space) + (answer space) + 1 = (answer space)
Answer: 49, 49, 99
- Double 49 is 98
- 98 + 1 = 99
4.29 + 8 = 29 + 1 + (answer space) = (answer space)
Answer: 7, 37
- 29 + 1 = 30 (a ten)
- 30 + 7 = 37
5.55 + 9 = 55 + 10 − (answer space) = (answer space)
Answer: 1, 64
- 55 + 10 = 65
- 65 − 1 = 64
6.42 + 41 = (answer space) + (answer space) + 1 = (answer space)
Answer: 41, 41, 83
- Double 41 is 82
- 82 + 1 = 83
7.37 + 7 = 37 + 3 + (answer space) = (answer space)
Answer: 4, 44
- 37 + 3 = 40 (a ten)
- 40 + 4 = 44
8.54 + 9 = 54 + 10 − (answer space) = (answer space)
Answer: 1, 63
- 54 + 10 = 64
- 64 − 1 = 63
9.22 + 21 = (answer space) + (answer space) + 1 = (answer space)
Answer: 21, 21, 43
- Double 21 is 42
- 42 + 1 = 43
10.65 + 6 = 65 + 5 + (answer space) = (answer space)
Answer: 1, 71
- 65 + 5 = 70 (a ten)
- 70 + 1 = 71
11.39 + 9 = 39 + 10 − (answer space) = (answer space)
Answer: 1, 48
- 39 + 10 = 49
- 49 − 1 = 48
12.45 + 46 = (answer space) + (answer space) + 1 = (answer space)
Answer: 45, 45, 91
- Double 45 is 90
- 90 + 1 = 91
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.