Year 4 Mental Addition and Subtraction Strategies Worksheet — Level 2 — Practice Set 2 — 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 2 — Answers
Fill in each step of the strategy, then write the answer.
1.35 + 9 = 35 + 5 + (answer space) = (answer space)
Answer: 4, 44
- 35 + 5 = 40 (a ten)
- 40 + 4 = 44
2.81 + 9 = 81 + 10 − (answer space) = (answer space)
Answer: 1, 90
- 81 + 10 = 91
- 91 − 1 = 90
3.46 + 45 = (answer space) + (answer space) + 1 = (answer space)
Answer: 45, 45, 91
- Double 45 is 90
- 90 + 1 = 91
4.58 + 8 = 58 + 2 + (answer space) = (answer space)
Answer: 6, 66
- 58 + 2 = 60 (a ten)
- 60 + 6 = 66
5.64 + 9 = 64 + 10 − (answer space) = (answer space)
Answer: 1, 73
- 64 + 10 = 74
- 74 − 1 = 73
6.73 + 72 = (answer space) + (answer space) + 1 = (answer space)
Answer: 72, 72, 145
- Double 72 is 144
- 144 + 1 = 145
7.67 + 8 = 67 + 3 + (answer space) = (answer space)
Answer: 5, 75
- 67 + 3 = 70 (a ten)
- 70 + 5 = 75
8.27 + 9 = 27 + 10 − (answer space) = (answer space)
Answer: 1, 36
- 27 + 10 = 37
- 37 − 1 = 36
9.28 + 29 = (answer space) + (answer space) + 1 = (answer space)
Answer: 28, 28, 57
- Double 28 is 56
- 56 + 1 = 57
10.87 + 8 = 87 + 3 + (answer space) = (answer space)
Answer: 5, 95
- 87 + 3 = 90 (a ten)
- 90 + 5 = 95
11.19 + 9 = 19 + 10 − (answer space) = (answer space)
Answer: 1, 28
- 19 + 10 = 29
- 29 − 1 = 28
12.52 + 51 = (answer space) + (answer space) + 1 = (answer space)
Answer: 51, 51, 103
- Double 51 is 102
- 102 + 1 = 103
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.