3rd Grade Estimating Sums, Differences and Products Worksheet — Level 1 — 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 1 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 78 − 12 by rounding each number to the nearest 10.
Answer: 70
- 78 rounds to 80; 12 rounds to 10
- 80 − 10 = 70
The exact answer is 66, close to the estimate.
2.Estimate 85 + 63 by rounding each number to the nearest 10.
Answer: 150
- 85 rounds to 90; 63 rounds to 60
- 90 + 60 = 150
The exact answer is 148, close to the estimate.
3.Estimate 73 + 72 by rounding each number to the nearest 10.
Answer: 140
- 73 rounds to 70; 72 rounds to 70
- 70 + 70 = 140
The exact answer is 145, close to the estimate.
4.Estimate 93 + 99 by rounding each number to the nearest 10.
Answer: 190
- 93 rounds to 90; 99 rounds to 100
- 90 + 100 = 190
The exact answer is 192, close to the estimate.
5.Estimate 85 − 27 by rounding each number to the nearest 10.
Answer: 60
- 85 rounds to 90; 27 rounds to 30
- 90 − 30 = 60
The exact answer is 58, close to the estimate.
6.Estimate 98 − 77 by rounding each number to the nearest 10.
Answer: 20
- 98 rounds to 100; 77 rounds to 80
- 100 − 80 = 20
The exact answer is 21, close to the estimate.
7.Estimate 53 − 43 by rounding each number to the nearest 10.
Answer: 10
- 53 rounds to 50; 43 rounds to 40
- 50 − 40 = 10
The exact answer is 10, close to the estimate.
8.Estimate 75 + 33 by rounding each number to the nearest 10.
Answer: 110
- 75 rounds to 80; 33 rounds to 30
- 80 + 30 = 110
The exact answer is 108, close to the estimate.
9.Estimate 78 + 96 by rounding each number to the nearest 10.
Answer: 180
- 78 rounds to 80; 96 rounds to 100
- 80 + 100 = 180
The exact answer is 174, close to the estimate.
10.Estimate 95 + 36 by rounding each number to the nearest 10.
Answer: 140
- 95 rounds to 100; 36 rounds to 40
- 100 + 40 = 140
The exact answer is 131, close to the estimate.
Marking tips
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