Year 5 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 5 place value worksheet.
Success TutoringWorksheetsAnswer sheetYear 5 · Mathematics · Place ValueYear 5 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 4 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 15 + 35 by rounding each number to the nearest 10.
Answer: 60
- 15 rounds to 20; 35 rounds to 40
- 20 + 40 = 60
The exact answer is 50, close to the estimate.
2.Estimate 48 − 39 by rounding each number to the nearest 10.
Answer: 10
- 48 rounds to 50; 39 rounds to 40
- 50 − 40 = 10
The exact answer is 9, close to the estimate.
3.Estimate 83 − 66 by rounding each number to the nearest 10.
Answer: 10
- 83 rounds to 80; 66 rounds to 70
- 80 − 70 = 10
The exact answer is 17, close to the estimate.
4.Estimate 65 − 27 by rounding each number to the nearest 10.
Answer: 40
- 65 rounds to 70; 27 rounds to 30
- 70 − 30 = 40
The exact answer is 38, close to the estimate.
5.Estimate 91 + 14 by rounding each number to the nearest 10.
Answer: 100
- 91 rounds to 90; 14 rounds to 10
- 90 + 10 = 100
The exact answer is 105, close to the estimate.
6.Estimate 98 − 91 by rounding each number to the nearest 10.
Answer: 10
- 98 rounds to 100; 91 rounds to 90
- 100 − 90 = 10
The exact answer is 7, close to the estimate.
7.Estimate 94 − 68 by rounding each number to the nearest 10.
Answer: 20
- 94 rounds to 90; 68 rounds to 70
- 90 − 70 = 20
The exact answer is 26, close to the estimate.
8.Estimate 88 − 65 by rounding each number to the nearest 10.
Answer: 20
- 88 rounds to 90; 65 rounds to 70
- 90 − 70 = 20
The exact answer is 23, close to the estimate.
9.Estimate 87 + 92 by rounding each number to the nearest 10.
Answer: 180
- 87 rounds to 90; 92 rounds to 90
- 90 + 90 = 180
The exact answer is 179, close to the estimate.
10.Estimate 94 − 28 by rounding each number to the nearest 10.
Answer: 60
- 94 rounds to 90; 28 rounds to 30
- 90 − 30 = 60
The exact answer is 66, 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.