Year 7 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 3 — 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 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 12 + 45 by rounding each number to the nearest 10.
Answer: 60
- 12 rounds to 10; 45 rounds to 50
- 10 + 50 = 60
The exact answer is 57, close to the estimate.
2.Estimate 95 + 39 by rounding each number to the nearest 10.
Answer: 140
- 95 rounds to 100; 39 rounds to 40
- 100 + 40 = 140
The exact answer is 134, close to the estimate.
3.Estimate 62 − 53 by rounding each number to the nearest 10.
Answer: 10
- 62 rounds to 60; 53 rounds to 50
- 60 − 50 = 10
The exact answer is 9, close to the estimate.
4.Estimate 49 + 42 by rounding each number to the nearest 10.
Answer: 90
- 49 rounds to 50; 42 rounds to 40
- 50 + 40 = 90
The exact answer is 91, close to the estimate.
5.Estimate 31 − 12 by rounding each number to the nearest 10.
Answer: 20
- 31 rounds to 30; 12 rounds to 10
- 30 − 10 = 20
The exact answer is 19, close to the estimate.
6.Estimate 77 − 51 by rounding each number to the nearest 10.
Answer: 30
- 77 rounds to 80; 51 rounds to 50
- 80 − 50 = 30
The exact answer is 26, close to the estimate.
7.Estimate 74 + 41 by rounding each number to the nearest 10.
Answer: 110
- 74 rounds to 70; 41 rounds to 40
- 70 + 40 = 110
The exact answer is 115, close to the estimate.
8.Estimate 35 + 47 by rounding each number to the nearest 10.
Answer: 90
- 35 rounds to 40; 47 rounds to 50
- 40 + 50 = 90
The exact answer is 82, close to the estimate.
9.Estimate 95 + 96 by rounding each number to the nearest 10.
Answer: 200
- 95 rounds to 100; 96 rounds to 100
- 100 + 100 = 200
The exact answer is 191, close to the estimate.
10.Estimate 56 − 28 by rounding each number to the nearest 10.
Answer: 30
- 56 rounds to 60; 28 rounds to 30
- 60 − 30 = 30
The exact answer is 28, 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.