Year 3 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 3 addition worksheet.
Success TutoringWorksheetsAnswer sheetYear 3 · Mathematics · AdditionYear 3 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 4 — Answers
Fill in each step of the strategy, then write the answer.
1.76 + 9 = 76 + 4 + (answer space) = (answer space)
Answer: 5, 85
- 76 + 4 = 80 (a ten)
- 80 + 5 = 85
2.83 + 9 = 83 + 10 − (answer space) = (answer space)
Answer: 1, 92
- 83 + 10 = 93
- 93 − 1 = 92
3.82 + 81 = (answer space) + (answer space) + 1 = (answer space)
Answer: 81, 81, 163
- Double 81 is 162
- 162 + 1 = 163
4.49 + 7 = 49 + 1 + (answer space) = (answer space)
Answer: 6, 56
- 49 + 1 = 50 (a ten)
- 50 + 6 = 56
5.29 + 9 = 29 + 10 − (answer space) = (answer space)
Answer: 1, 38
- 29 + 10 = 39
- 39 − 1 = 38
6.25 + 24 = (answer space) + (answer space) + 1 = (answer space)
Answer: 24, 24, 49
- Double 24 is 48
- 48 + 1 = 49
7.55 + 9 = 55 + 5 + (answer space) = (answer space)
Answer: 4, 64
- 55 + 5 = 60 (a ten)
- 60 + 4 = 64
8.76 + 9 = 76 + 10 − (answer space) = (answer space)
Answer: 1, 85
- 76 + 10 = 86
- 86 − 1 = 85
9.17 + 18 = (answer space) + (answer space) + 1 = (answer space)
Answer: 17, 17, 35
- Double 17 is 34
- 34 + 1 = 35
10.65 + 9 = 65 + 5 + (answer space) = (answer space)
Answer: 4, 74
- 65 + 5 = 70 (a ten)
- 70 + 4 = 74
11.24 + 9 = 24 + 10 − (answer space) = (answer space)
Answer: 1, 33
- 24 + 10 = 34
- 34 − 1 = 33
12.15 + 14 = (answer space) + (answer space) + 1 = (answer space)
Answer: 14, 14, 29
- Double 14 is 28
- 28 + 1 = 29
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.