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.
1.65 + 9 = 65 + 5 + (answer space) = (answer space)
Answer: 4, 74
- 65 + 5 = 70 (a ten)
- 70 + 4 = 74
2.64 + 9 = 64 + 10 − (answer space) = (answer space)
Answer: 1, 73
- 64 + 10 = 74
- 74 − 1 = 73
3.83 + 82 = (answer space) + (answer space) + 1 = (answer space)
Answer: 82, 82, 165
- Double 82 is 164
- 164 + 1 = 165
4.58 + 5 = 58 + 2 + (answer space) = (answer space)
Answer: 3, 63
- 58 + 2 = 60 (a ten)
- 60 + 3 = 63
5.15 + 9 = 15 + 10 − (answer space) = (answer space)
Answer: 1, 24
- 15 + 10 = 25
- 25 − 1 = 24
6.37 + 36 = (answer space) + (answer space) + 1 = (answer space)
Answer: 36, 36, 73
- Double 36 is 72
- 72 + 1 = 73
7.58 + 8 = 58 + 2 + (answer space) = (answer space)
Answer: 6, 66
- 58 + 2 = 60 (a ten)
- 60 + 6 = 66
8.48 + 9 = 48 + 10 − (answer space) = (answer space)
Answer: 1, 57
- 48 + 10 = 58
- 58 − 1 = 57
9.12 + 13 = (answer space) + (answer space) + 1 = (answer space)
Answer: 12, 12, 25
- Double 12 is 24
- 24 + 1 = 25
10.16 + 8 = 16 + 4 + (answer space) = (answer space)
Answer: 4, 24
- 16 + 4 = 20 (a ten)
- 20 + 4 = 24
11.63 + 9 = 63 + 10 − (answer space) = (answer space)
Answer: 1, 72
- 63 + 10 = 73
- 73 − 1 = 72
12.80 + 81 = (answer space) + (answer space) + 1 = (answer space)
Answer: 80, 80, 161
- Double 80 is 160
- 160 + 1 = 161
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.