Year 5 Estimating Sums, Differences and Products Worksheet — Level 3 — Practice Set 3 — 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 3 — Practice Set 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 7,730 − 5,961 by rounding each number to the nearest 100.
Answer: 1,700
- 7,730 rounds to 7,700; 5,961 rounds to 6,000
- 7,700 − 6,000 = 1,700
The exact answer is 1,769, close to the estimate.
2.Estimate 78 × 47 by rounding each number to the nearest 10.
Answer: 4,000
- 78 rounds to 80; 47 rounds to 50
- 80 × 50 = 4,000
The exact answer is 3,666.
3.Estimate 54 × 4 by rounding 54 to the nearest 10.
Answer: 200
- 54 rounds to 50
- 50 × 4 = 200
The exact answer is 216.
4.Estimate 6,653 − 4,944 by rounding each number to the nearest 100.
Answer: 1,800
- 6,653 rounds to 6,700; 4,944 rounds to 4,900
- 6,700 − 4,900 = 1,800
The exact answer is 1,709, close to the estimate.
5.Estimate 54 × 42 by rounding each number to the nearest 10.
Answer: 2,000
- 54 rounds to 50; 42 rounds to 40
- 50 × 40 = 2,000
The exact answer is 2,268.
6.Estimate 42 × 6 by rounding 42 to the nearest 10.
Answer: 240
- 42 rounds to 40
- 40 × 6 = 240
The exact answer is 252.
7.Estimate 9,551 − 5,613 by rounding each number to the nearest 1,000.
Answer: 4,000
- 9,551 rounds to 10,000; 5,613 rounds to 6,000
- 10,000 − 6,000 = 4,000
The exact answer is 3,938, close to the estimate.
8.Estimate 16 × 98 by rounding each number to the nearest 10.
Answer: 2,000
- 16 rounds to 20; 98 rounds to 100
- 20 × 100 = 2,000
The exact answer is 1,568.
9.Estimate 99 × 9 by rounding 99 to the nearest 10.
Answer: 900
- 99 rounds to 100
- 100 × 9 = 900
The exact answer is 891.
10.Estimate 8,487 − 6,237 by rounding each number to the nearest 1,000.
Answer: 2,000
- 8,487 rounds to 8,000; 6,237 rounds to 6,000
- 8,000 − 6,000 = 2,000
The exact answer is 2,250, close to the estimate.
Marking tips
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