3rd Grade Estimating Sums, Differences and Products Worksheet — Level 1 — Practice Set 4 — 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 — Practice Set 4 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 91 − 47 by rounding each number to the nearest 10.
Answer: 40
- 91 rounds to 90; 47 rounds to 50
- 90 − 50 = 40
The exact answer is 44, close to the estimate.
2.Estimate 73 − 15 by rounding each number to the nearest 10.
Answer: 50
- 73 rounds to 70; 15 rounds to 20
- 70 − 20 = 50
The exact answer is 58, close to the estimate.
3.Estimate 97 − 17 by rounding each number to the nearest 10.
Answer: 80
- 97 rounds to 100; 17 rounds to 20
- 100 − 20 = 80
The exact answer is 80, close to the estimate.
4.Estimate 49 − 22 by rounding each number to the nearest 10.
Answer: 30
- 49 rounds to 50; 22 rounds to 20
- 50 − 20 = 30
The exact answer is 27, close to the estimate.
5.Estimate 97 + 71 by rounding each number to the nearest 10.
Answer: 170
- 97 rounds to 100; 71 rounds to 70
- 100 + 70 = 170
The exact answer is 168, close to the estimate.
6.Estimate 71 + 39 by rounding each number to the nearest 10.
Answer: 110
- 71 rounds to 70; 39 rounds to 40
- 70 + 40 = 110
The exact answer is 110, close to the estimate.
7.Estimate 91 − 56 by rounding each number to the nearest 10.
Answer: 30
- 91 rounds to 90; 56 rounds to 60
- 90 − 60 = 30
The exact answer is 35, close to the estimate.
8.Estimate 97 − 44 by rounding each number to the nearest 10.
Answer: 60
- 97 rounds to 100; 44 rounds to 40
- 100 − 40 = 60
The exact answer is 53, close to the estimate.
9.Estimate 74 − 61 by rounding each number to the nearest 10.
Answer: 10
- 74 rounds to 70; 61 rounds to 60
- 70 − 60 = 10
The exact answer is 13, close to the estimate.
10.Estimate 59 − 47 by rounding each number to the nearest 10.
Answer: 10
- 59 rounds to 60; 47 rounds to 50
- 60 − 50 = 10
The exact answer is 12, close to the estimate.
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.