Year 7 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 7 place value worksheet.
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · Place ValueYear 7 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 2 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 72 − 43 by rounding each number to the nearest 10.
Answer: 30
- 72 rounds to 70; 43 rounds to 40
- 70 − 40 = 30
The exact answer is 29, close to the estimate.
2.Estimate 95 − 61 by rounding each number to the nearest 10.
Answer: 40
- 95 rounds to 100; 61 rounds to 60
- 100 − 60 = 40
The exact answer is 34, close to the estimate.
3.Estimate 25 + 38 by rounding each number to the nearest 10.
Answer: 70
- 25 rounds to 30; 38 rounds to 40
- 30 + 40 = 70
The exact answer is 63, close to the estimate.
4.Estimate 93 + 13 by rounding each number to the nearest 10.
Answer: 100
- 93 rounds to 90; 13 rounds to 10
- 90 + 10 = 100
The exact answer is 106, close to the estimate.
5.Estimate 55 − 47 by rounding each number to the nearest 10.
Answer: 10
- 55 rounds to 60; 47 rounds to 50
- 60 − 50 = 10
The exact answer is 8, close to the estimate.
6.Estimate 52 + 29 by rounding each number to the nearest 10.
Answer: 80
- 52 rounds to 50; 29 rounds to 30
- 50 + 30 = 80
The exact answer is 81, close to the estimate.
7.Estimate 86 − 35 by rounding each number to the nearest 10.
Answer: 50
- 86 rounds to 90; 35 rounds to 40
- 90 − 40 = 50
The exact answer is 51, close to the estimate.
8.Estimate 42 + 59 by rounding each number to the nearest 10.
Answer: 100
- 42 rounds to 40; 59 rounds to 60
- 40 + 60 = 100
The exact answer is 101, close to the estimate.
9.Estimate 85 − 46 by rounding each number to the nearest 10.
Answer: 40
- 85 rounds to 90; 46 rounds to 50
- 90 − 50 = 40
The exact answer is 39, close to the estimate.
10.Estimate 96 + 78 by rounding each number to the nearest 10.
Answer: 180
- 96 rounds to 100; 78 rounds to 80
- 100 + 80 = 180
The exact answer is 174, close to the estimate.
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.