Year 3 Estimating Sums, Differences and Products Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 3 place value worksheet.
Success TutoringWorksheetsAnswer sheetYear 3 · Mathematics · Place ValueYear 3 Estimating Sums, Differences and Products Worksheet — Level 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 2,810 + 7,415 by rounding each number to the nearest 100.
Answer: 10,200
- 2,810 rounds to 2,800; 7,415 rounds to 7,400
- 2,800 + 7,400 = 10,200
The exact answer is 10,225, close to the estimate.
2.Estimate 86 × 75 by rounding each number to the nearest 10.
Answer: 7,200
- 86 rounds to 90; 75 rounds to 80
- 90 × 80 = 7,200
The exact answer is 6,450.
3.Estimate 32 × 91 by rounding each number to the nearest 10.
Answer: 2,700
- 32 rounds to 30; 91 rounds to 90
- 30 × 90 = 2,700
The exact answer is 2,912.
4.Estimate 7,949 − 5,165 by rounding each number to the nearest 100.
Answer: 2,700
- 7,949 rounds to 7,900; 5,165 rounds to 5,200
- 7,900 − 5,200 = 2,700
The exact answer is 2,784, close to the estimate.
5.Estimate 96 × 57 by rounding each number to the nearest 10.
Answer: 6,000
- 96 rounds to 100; 57 rounds to 60
- 100 × 60 = 6,000
The exact answer is 5,472.
6.Estimate 16 × 8 by rounding 16 to the nearest 10.
Answer: 160
- 16 rounds to 20
- 20 × 8 = 160
The exact answer is 128.
7.Estimate 8,875 + 4,111 by rounding each number to the nearest 100.
Answer: 13,000
- 8,875 rounds to 8,900; 4,111 rounds to 4,100
- 8,900 + 4,100 = 13,000
The exact answer is 12,986, close to the estimate.
8.Estimate 82 × 14 by rounding each number to the nearest 10.
Answer: 800
- 82 rounds to 80; 14 rounds to 10
- 80 × 10 = 800
The exact answer is 1,148.
9.Estimate 98 × 8 by rounding 98 to the nearest 10.
Answer: 800
- 98 rounds to 100
- 100 × 8 = 800
The exact answer is 784.
10.Estimate 8,568 − 7,436 by rounding each number to the nearest 100.
Answer: 1,200
- 8,568 rounds to 8,600; 7,436 rounds to 7,400
- 8,600 − 7,400 = 1,200
The exact answer is 1,132, 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.