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.
1.89 + 8 = 89 + 1 + (answer space) = (answer space)
Answer: 7, 97
- 89 + 1 = 90 (a ten)
- 90 + 7 = 97
2.48 + 9 = 48 + 10 − (answer space) = (answer space)
Answer: 1, 57
- 48 + 10 = 58
- 58 − 1 = 57
3.73 + 72 = (answer space) + (answer space) + 1 = (answer space)
Answer: 72, 72, 145
- Double 72 is 144
- 144 + 1 = 145
4.47 + 6 = 47 + 3 + (answer space) = (answer space)
Answer: 3, 53
- 47 + 3 = 50 (a ten)
- 50 + 3 = 53
5.23 + 9 = 23 + 10 − (answer space) = (answer space)
Answer: 1, 32
- 23 + 10 = 33
- 33 − 1 = 32
6.27 + 26 = (answer space) + (answer space) + 1 = (answer space)
Answer: 26, 26, 53
- Double 26 is 52
- 52 + 1 = 53
7.87 + 6 = 87 + 3 + (answer space) = (answer space)
Answer: 3, 93
- 87 + 3 = 90 (a ten)
- 90 + 3 = 93
8.19 + 9 = 19 + 10 − (answer space) = (answer space)
Answer: 1, 28
- 19 + 10 = 29
- 29 − 1 = 28
9.30 + 29 = (answer space) + (answer space) + 1 = (answer space)
Answer: 29, 29, 59
- Double 29 is 58
- 58 + 1 = 59
10.47 + 9 = 47 + 3 + (answer space) = (answer space)
Answer: 6, 56
- 47 + 3 = 50 (a ten)
- 50 + 6 = 56
11.74 + 9 = 74 + 10 − (answer space) = (answer space)
Answer: 1, 83
- 74 + 10 = 84
- 84 − 1 = 83
12.24 + 25 = (answer space) + (answer space) + 1 = (answer space)
Answer: 24, 24, 49
- Double 24 is 48
- 48 + 1 = 49
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.