Year 3 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 2 — 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 1 — Practice Set 2 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 67 − 37 by rounding each number to the nearest 10.
Answer: 30
- 67 rounds to 70; 37 rounds to 40
- 70 − 40 = 30
The exact answer is 30, close to the estimate.
2.Estimate 89 − 53 by rounding each number to the nearest 10.
Answer: 40
- 89 rounds to 90; 53 rounds to 50
- 90 − 50 = 40
The exact answer is 36, close to the estimate.
3.Estimate 79 + 14 by rounding each number to the nearest 10.
Answer: 90
- 79 rounds to 80; 14 rounds to 10
- 80 + 10 = 90
The exact answer is 93, close to the estimate.
4.Estimate 81 − 72 by rounding each number to the nearest 10.
Answer: 10
- 81 rounds to 80; 72 rounds to 70
- 80 − 70 = 10
The exact answer is 9, close to the estimate.
5.Estimate 34 + 85 by rounding each number to the nearest 10.
Answer: 120
- 34 rounds to 30; 85 rounds to 90
- 30 + 90 = 120
The exact answer is 119, close to the estimate.
6.Estimate 76 + 49 by rounding each number to the nearest 10.
Answer: 130
- 76 rounds to 80; 49 rounds to 50
- 80 + 50 = 130
The exact answer is 125, close to the estimate.
7.Estimate 95 + 31 by rounding each number to the nearest 10.
Answer: 130
- 95 rounds to 100; 31 rounds to 30
- 100 + 30 = 130
The exact answer is 126, close to the estimate.
8.Estimate 51 + 79 by rounding each number to the nearest 10.
Answer: 130
- 51 rounds to 50; 79 rounds to 80
- 50 + 80 = 130
The exact answer is 130, close to the estimate.
9.Estimate 86 + 69 by rounding each number to the nearest 10.
Answer: 160
- 86 rounds to 90; 69 rounds to 70
- 90 + 70 = 160
The exact answer is 155, close to the estimate.
10.Estimate 42 + 76 by rounding each number to the nearest 10.
Answer: 120
- 42 rounds to 40; 76 rounds to 80
- 40 + 80 = 120
The exact answer is 118, 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.