Year 4 Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 4 place value worksheet.
Success TutoringWorksheetsAnswer sheetYear 4 · Mathematics · Place ValueYear 4 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 84 − 27 by rounding each number to the nearest 10.
Answer: 50
- 84 rounds to 80; 27 rounds to 30
- 80 − 30 = 50
The exact answer is 57, close to the estimate.
2.Estimate 93 + 45 by rounding each number to the nearest 10.
Answer: 140
- 93 rounds to 90; 45 rounds to 50
- 90 + 50 = 140
The exact answer is 138, close to the estimate.
3.Estimate 73 + 49 by rounding each number to the nearest 10.
Answer: 120
- 73 rounds to 70; 49 rounds to 50
- 70 + 50 = 120
The exact answer is 122, close to the estimate.
4.Estimate 55 − 49 by rounding each number to the nearest 10.
Answer: 10
- 55 rounds to 60; 49 rounds to 50
- 60 − 50 = 10
The exact answer is 6, close to the estimate.
5.Estimate 83 − 24 by rounding each number to the nearest 10.
Answer: 60
- 83 rounds to 80; 24 rounds to 20
- 80 − 20 = 60
The exact answer is 59, close to the estimate.
6.Estimate 51 + 96 by rounding each number to the nearest 10.
Answer: 150
- 51 rounds to 50; 96 rounds to 100
- 50 + 100 = 150
The exact answer is 147, close to the estimate.
7.Estimate 29 + 99 by rounding each number to the nearest 10.
Answer: 130
- 29 rounds to 30; 99 rounds to 100
- 30 + 100 = 130
The exact answer is 128, close to the estimate.
8.Estimate 64 − 39 by rounding each number to the nearest 10.
Answer: 20
- 64 rounds to 60; 39 rounds to 40
- 60 − 40 = 20
The exact answer is 25, close to the estimate.
9.Estimate 77 − 13 by rounding each number to the nearest 10.
Answer: 70
- 77 rounds to 80; 13 rounds to 10
- 80 − 10 = 70
The exact answer is 64, close to the estimate.
10.Estimate 59 + 79 by rounding each number to the nearest 10.
Answer: 140
- 59 rounds to 60; 79 rounds to 80
- 60 + 80 = 140
The exact answer is 138, 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.