Year 3 Estimating Sums, Differences and Products Worksheet — Level 3 — Practice Set 3 — 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 3 — Practice Set 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 7,816 + 3,740 by rounding each number to the nearest 100.
Answer: 11,500
- 7,816 rounds to 7,800; 3,740 rounds to 3,700
- 7,800 + 3,700 = 11,500
The exact answer is 11,556, close to the estimate.
2.Estimate 29 × 77 by rounding each number to the nearest 10.
Answer: 2,400
- 29 rounds to 30; 77 rounds to 80
- 30 × 80 = 2,400
The exact answer is 2,233.
3.Estimate 64 × 28 by rounding each number to the nearest 10.
Answer: 1,800
- 64 rounds to 60; 28 rounds to 30
- 60 × 30 = 1,800
The exact answer is 1,792.
4.Estimate 4,016 − 3,203 by rounding each number to the nearest 1,000.
Answer: 1,000
- 4,016 rounds to 4,000; 3,203 rounds to 3,000
- 4,000 − 3,000 = 1,000
The exact answer is 813, close to the estimate.
5.Estimate 17 × 35 by rounding each number to the nearest 10.
Answer: 800
- 17 rounds to 20; 35 rounds to 40
- 20 × 40 = 800
The exact answer is 595.
6.Estimate 39 × 4 by rounding 39 to the nearest 10.
Answer: 160
- 39 rounds to 40
- 40 × 4 = 160
The exact answer is 156.
7.Estimate 9,383 + 3,349 by rounding each number to the nearest 100.
Answer: 12,700
- 9,383 rounds to 9,400; 3,349 rounds to 3,300
- 9,400 + 3,300 = 12,700
The exact answer is 12,732, close to the estimate.
8.Estimate 91 × 96 by rounding each number to the nearest 10.
Answer: 9,000
- 91 rounds to 90; 96 rounds to 100
- 90 × 100 = 9,000
The exact answer is 8,736.
9.Estimate 12 × 4 by rounding 12 to the nearest 10.
Answer: 40
- 12 rounds to 10
- 10 × 4 = 40
The exact answer is 48.
10.Estimate 3,143 + 2,706 by rounding each number to the nearest 1,000.
Answer: 6,000
- 3,143 rounds to 3,000; 2,706 rounds to 3,000
- 3,000 + 3,000 = 6,000
The exact answer is 5,849, close to the estimate.
Marking tips
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