Year 4 Estimating Sums, Differences and Products Worksheet — Level 1 — 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 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 87 − 77 by rounding each number to the nearest 10.
Answer: 10
- 87 rounds to 90; 77 rounds to 80
- 90 − 80 = 10
The exact answer is 10, close to the estimate.
2.Estimate 48 + 51 by rounding each number to the nearest 10.
Answer: 100
- 48 rounds to 50; 51 rounds to 50
- 50 + 50 = 100
The exact answer is 99, close to the estimate.
3.Estimate 86 − 56 by rounding each number to the nearest 10.
Answer: 30
- 86 rounds to 90; 56 rounds to 60
- 90 − 60 = 30
The exact answer is 30, close to the estimate.
4.Estimate 35 + 23 by rounding each number to the nearest 10.
Answer: 60
- 35 rounds to 40; 23 rounds to 20
- 40 + 20 = 60
The exact answer is 58, close to the estimate.
5.Estimate 24 + 71 by rounding each number to the nearest 10.
Answer: 90
- 24 rounds to 20; 71 rounds to 70
- 20 + 70 = 90
The exact answer is 95, close to the estimate.
6.Estimate 66 + 91 by rounding each number to the nearest 10.
Answer: 160
- 66 rounds to 70; 91 rounds to 90
- 70 + 90 = 160
The exact answer is 157, close to the estimate.
7.Estimate 23 − 12 by rounding each number to the nearest 10.
Answer: 10
- 23 rounds to 20; 12 rounds to 10
- 20 − 10 = 10
The exact answer is 11, close to the estimate.
8.Estimate 27 + 42 by rounding each number to the nearest 10.
Answer: 70
- 27 rounds to 30; 42 rounds to 40
- 30 + 40 = 70
The exact answer is 69, close to the estimate.
9.Estimate 51 + 87 by rounding each number to the nearest 10.
Answer: 140
- 51 rounds to 50; 87 rounds to 90
- 50 + 90 = 140
The exact answer is 138, close to the estimate.
10.Estimate 58 − 49 by rounding each number to the nearest 10.
Answer: 10
- 58 rounds to 60; 49 rounds to 50
- 60 − 50 = 10
The exact answer is 9, close to the estimate.
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