3rd Grade Estimating Sums, Differences and Products Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 3rd Grade place value worksheet.
Success TutoringWorksheetsAnswer sheet3rd Grade · Mathematics · Place Value3rd Grade 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 9,638 − 9,222 by rounding each number to the nearest 1,000.
Answer: 1,000
- 9,638 rounds to 10,000; 9,222 rounds to 9,000
- 10,000 − 9,000 = 1,000
The exact answer is 416, close to the estimate.
2.Estimate 18 × 58 by rounding each number to the nearest 10.
Answer: 1,200
- 18 rounds to 20; 58 rounds to 60
- 20 × 60 = 1,200
The exact answer is 1,044.
3.Estimate 52 × 7 by rounding 52 to the nearest 10.
Answer: 350
- 52 rounds to 50
- 50 × 7 = 350
The exact answer is 364.
4.Estimate 7,731 + 7,167 by rounding each number to the nearest 100.
Answer: 14,900
- 7,731 rounds to 7,700; 7,167 rounds to 7,200
- 7,700 + 7,200 = 14,900
The exact answer is 14,898, close to the estimate.
5.Estimate 34 × 19 by rounding each number to the nearest 10.
Answer: 600
- 34 rounds to 30; 19 rounds to 20
- 30 × 20 = 600
The exact answer is 646.
6.Estimate 45 × 9 by rounding 45 to the nearest 10.
Answer: 450
- 45 rounds to 50
- 50 × 9 = 450
The exact answer is 405.
7.Estimate 7,798 − 6,580 by rounding each number to the nearest 100.
Answer: 1,200
- 7,798 rounds to 7,800; 6,580 rounds to 6,600
- 7,800 − 6,600 = 1,200
The exact answer is 1,218, close to the estimate.
8.Estimate 29 × 44 by rounding each number to the nearest 10.
Answer: 1,200
- 29 rounds to 30; 44 rounds to 40
- 30 × 40 = 1,200
The exact answer is 1,276.
9.Estimate 17 × 9 by rounding 17 to the nearest 10.
Answer: 180
- 17 rounds to 20
- 20 × 9 = 180
The exact answer is 153.
10.Estimate 5,839 − 1,264 by rounding each number to the nearest 100.
Answer: 4,500
- 5,839 rounds to 5,800; 1,264 rounds to 1,300
- 5,800 − 1,300 = 4,500
The exact answer is 4,575, close to the estimate.
Marking tips
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