Year 3 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 2 — 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 2 — Answers
Fill in each step of the strategy, then write the answer.
1.89 + 8 = 89 + 1 + (answer space) = (answer space)
Answer: 7, 97
- 89 + 1 = 90 (a ten)
- 90 + 7 = 97
2.61 + 9 = 61 + 10 − (answer space) = (answer space)
Answer: 1, 70
- 61 + 10 = 71
- 71 − 1 = 70
3.48 + 47 = (answer space) + (answer space) + 1 = (answer space)
Answer: 47, 47, 95
- Double 47 is 94
- 94 + 1 = 95
4.76 + 5 = 76 + 4 + (answer space) = (answer space)
Answer: 1, 81
- 76 + 4 = 80 (a ten)
- 80 + 1 = 81
5.63 + 9 = 63 + 10 − (answer space) = (answer space)
Answer: 1, 72
- 63 + 10 = 73
- 73 − 1 = 72
6.53 + 54 = (answer space) + (answer space) + 1 = (answer space)
Answer: 53, 53, 107
- Double 53 is 106
- 106 + 1 = 107
7.15 + 7 = 15 + 5 + (answer space) = (answer space)
Answer: 2, 22
- 15 + 5 = 20 (a ten)
- 20 + 2 = 22
8.87 + 9 = 87 + 10 − (answer space) = (answer space)
Answer: 1, 96
- 87 + 10 = 97
- 97 − 1 = 96
9.51 + 50 = (answer space) + (answer space) + 1 = (answer space)
Answer: 50, 50, 101
- Double 50 is 100
- 100 + 1 = 101
10.86 + 5 = 86 + 4 + (answer space) = (answer space)
Answer: 1, 91
- 86 + 4 = 90 (a ten)
- 90 + 1 = 91
11.78 + 9 = 78 + 10 − (answer space) = (answer space)
Answer: 1, 87
- 78 + 10 = 88
- 88 − 1 = 87
12.28 + 27 = (answer space) + (answer space) + 1 = (answer space)
Answer: 27, 27, 55
- Double 27 is 54
- 54 + 1 = 55
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.