Year 3 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 3 — 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 3 — Answers
Fill in each step of the strategy, then write the answer.
1.57 + 6 = 57 + 3 + (answer space) = (answer space)
Answer: 3, 63
- 57 + 3 = 60 (a ten)
- 60 + 3 = 63
2.53 + 9 = 53 + 10 − (answer space) = (answer space)
Answer: 1, 62
- 53 + 10 = 63
- 63 − 1 = 62
3.47 + 46 = (answer space) + (answer space) + 1 = (answer space)
Answer: 46, 46, 93
- Double 46 is 92
- 92 + 1 = 93
4.77 + 6 = 77 + 3 + (answer space) = (answer space)
Answer: 3, 83
- 77 + 3 = 80 (a ten)
- 80 + 3 = 83
5.68 + 9 = 68 + 10 − (answer space) = (answer space)
Answer: 1, 77
- 68 + 10 = 78
- 78 − 1 = 77
6.75 + 74 = (answer space) + (answer space) + 1 = (answer space)
Answer: 74, 74, 149
- Double 74 is 148
- 148 + 1 = 149
7.59 + 7 = 59 + 1 + (answer space) = (answer space)
Answer: 6, 66
- 59 + 1 = 60 (a ten)
- 60 + 6 = 66
8.19 + 9 = 19 + 10 − (answer space) = (answer space)
Answer: 1, 28
- 19 + 10 = 29
- 29 − 1 = 28
9.71 + 72 = (answer space) + (answer space) + 1 = (answer space)
Answer: 71, 71, 143
- Double 71 is 142
- 142 + 1 = 143
10.69 + 5 = 69 + 1 + (answer space) = (answer space)
Answer: 4, 74
- 69 + 1 = 70 (a ten)
- 70 + 4 = 74
11.42 + 9 = 42 + 10 − (answer space) = (answer space)
Answer: 1, 51
- 42 + 10 = 52
- 52 − 1 = 51
12.49 + 48 = (answer space) + (answer space) + 1 = (answer space)
Answer: 48, 48, 97
- Double 48 is 96
- 96 + 1 = 97
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.