Year 7 Estimating Sums, Differences and Products Worksheet — Level 2 — 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 2 — Practice Set 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 717 + 853 by rounding each number to the nearest 100.
Answer: 1,600
- 717 rounds to 700; 853 rounds to 900
- 700 + 900 = 1,600
The exact answer is 1,570, close to the estimate.
2.Estimate 76 × 3 by rounding 76 to the nearest 10.
Answer: 240
- 76 rounds to 80
- 80 × 3 = 240
The exact answer is 228.
3.Estimate 763 + 449 by rounding each number to the nearest 100.
Answer: 1,200
- 763 rounds to 800; 449 rounds to 400
- 800 + 400 = 1,200
The exact answer is 1,212, close to the estimate.
4.Estimate 76 × 9 by rounding 76 to the nearest 10.
Answer: 720
- 76 rounds to 80
- 80 × 9 = 720
The exact answer is 684.
5.Estimate 990 − 215 by rounding each number to the nearest 100.
Answer: 800
- 990 rounds to 1,000; 215 rounds to 200
- 1,000 − 200 = 800
The exact answer is 775, close to the estimate.
6.Estimate 89 × 3 by rounding 89 to the nearest 10.
Answer: 270
- 89 rounds to 90
- 90 × 3 = 270
The exact answer is 267.
7.Estimate 609 − 515 by rounding each number to the nearest 100.
Answer: 100
- 609 rounds to 600; 515 rounds to 500
- 600 − 500 = 100
The exact answer is 94, close to the estimate.
8.Estimate 23 × 7 by rounding 23 to the nearest 10.
Answer: 140
- 23 rounds to 20
- 20 × 7 = 140
The exact answer is 161.
9.Estimate 769 − 505 by rounding each number to the nearest 100.
Answer: 300
- 769 rounds to 800; 505 rounds to 500
- 800 − 500 = 300
The exact answer is 264, close to the estimate.
10.Estimate 97 × 6 by rounding 97 to the nearest 10.
Answer: 600
- 97 rounds to 100
- 100 × 6 = 600
The exact answer is 582.
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.