Year 3 Estimating Sums, Differences and Products Worksheet — Level 1 — 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 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 65 + 26 by rounding each number to the nearest 10.
Answer: 100
- 65 rounds to 70; 26 rounds to 30
- 70 + 30 = 100
The exact answer is 91, close to the estimate.
2.Estimate 42 + 59 by rounding each number to the nearest 10.
Answer: 100
- 42 rounds to 40; 59 rounds to 60
- 40 + 60 = 100
The exact answer is 101, close to the estimate.
3.Estimate 93 − 81 by rounding each number to the nearest 10.
Answer: 10
- 93 rounds to 90; 81 rounds to 80
- 90 − 80 = 10
The exact answer is 12, close to the estimate.
4.Estimate 34 + 27 by rounding each number to the nearest 10.
Answer: 60
- 34 rounds to 30; 27 rounds to 30
- 30 + 30 = 60
The exact answer is 61, close to the estimate.
5.Estimate 98 − 43 by rounding each number to the nearest 10.
Answer: 60
- 98 rounds to 100; 43 rounds to 40
- 100 − 40 = 60
The exact answer is 55, close to the estimate.
6.Estimate 68 + 87 by rounding each number to the nearest 10.
Answer: 160
- 68 rounds to 70; 87 rounds to 90
- 70 + 90 = 160
The exact answer is 155, close to the estimate.
7.Estimate 42 + 81 by rounding each number to the nearest 10.
Answer: 120
- 42 rounds to 40; 81 rounds to 80
- 40 + 80 = 120
The exact answer is 123, close to the estimate.
8.Estimate 81 − 64 by rounding each number to the nearest 10.
Answer: 20
- 81 rounds to 80; 64 rounds to 60
- 80 − 60 = 20
The exact answer is 17, close to the estimate.
9.Estimate 89 − 18 by rounding each number to the nearest 10.
Answer: 70
- 89 rounds to 90; 18 rounds to 20
- 90 − 20 = 70
The exact answer is 71, close to the estimate.
10.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.
Marking tips
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