Year 5 Estimating Sums, Differences and Products Worksheet — Level 1 — 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 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 91 − 78 by rounding each number to the nearest 10.
Answer: 10
- 91 rounds to 90; 78 rounds to 80
- 90 − 80 = 10
The exact answer is 13, close to the estimate.
2.Estimate 76 − 59 by rounding each number to the nearest 10.
Answer: 20
- 76 rounds to 80; 59 rounds to 60
- 80 − 60 = 20
The exact answer is 17, close to the estimate.
3.Estimate 72 + 93 by rounding each number to the nearest 10.
Answer: 160
- 72 rounds to 70; 93 rounds to 90
- 70 + 90 = 160
The exact answer is 165, close to the estimate.
4.Estimate 68 + 57 by rounding each number to the nearest 10.
Answer: 130
- 68 rounds to 70; 57 rounds to 60
- 70 + 60 = 130
The exact answer is 125, close to the estimate.
5.Estimate 21 + 89 by rounding each number to the nearest 10.
Answer: 110
- 21 rounds to 20; 89 rounds to 90
- 20 + 90 = 110
The exact answer is 110, close to the estimate.
6.Estimate 97 − 33 by rounding each number to the nearest 10.
Answer: 70
- 97 rounds to 100; 33 rounds to 30
- 100 − 30 = 70
The exact answer is 64, close to the estimate.
7.Estimate 63 + 98 by rounding each number to the nearest 10.
Answer: 160
- 63 rounds to 60; 98 rounds to 100
- 60 + 100 = 160
The exact answer is 161, close to the estimate.
8.Estimate 78 − 46 by rounding each number to the nearest 10.
Answer: 30
- 78 rounds to 80; 46 rounds to 50
- 80 − 50 = 30
The exact answer is 32, close to the estimate.
9.Estimate 91 + 87 by rounding each number to the nearest 10.
Answer: 180
- 91 rounds to 90; 87 rounds to 90
- 90 + 90 = 180
The exact answer is 178, close to the estimate.
10.Estimate 77 − 19 by rounding each number to the nearest 10.
Answer: 60
- 77 rounds to 80; 19 rounds to 20
- 80 − 20 = 60
The exact answer is 58, close to the estimate.
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