3rd Grade Estimating Sums, Differences and Products Worksheet — Level 2 — 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 2 — Practice Set 4 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 412 + 827 by rounding each number to the nearest 100.
Answer: 1,200
- 412 rounds to 400; 827 rounds to 800
- 400 + 800 = 1,200
The exact answer is 1,239, close to the estimate.
2.Estimate 86 × 8 by rounding 86 to the nearest 10.
Answer: 720
- 86 rounds to 90
- 90 × 8 = 720
The exact answer is 688.
3.Estimate 652 − 256 by rounding each number to the nearest 100.
Answer: 400
- 652 rounds to 700; 256 rounds to 300
- 700 − 300 = 400
The exact answer is 396, close to the estimate.
4.Estimate 19 × 4 by rounding 19 to the nearest 10.
Answer: 80
- 19 rounds to 20
- 20 × 4 = 80
The exact answer is 76.
5.Estimate 875 − 650 by rounding each number to the nearest 100.
Answer: 200
- 875 rounds to 900; 650 rounds to 700
- 900 − 700 = 200
The exact answer is 225, close to the estimate.
6.Estimate 87 × 6 by rounding 87 to the nearest 10.
Answer: 540
- 87 rounds to 90
- 90 × 6 = 540
The exact answer is 522.
7.Estimate 948 − 282 by rounding each number to the nearest 100.
Answer: 600
- 948 rounds to 900; 282 rounds to 300
- 900 − 300 = 600
The exact answer is 666, close to the estimate.
8.Estimate 87 × 7 by rounding 87 to the nearest 10.
Answer: 630
- 87 rounds to 90
- 90 × 7 = 630
The exact answer is 609.
9.Estimate 821 − 161 by rounding each number to the nearest 100.
Answer: 600
- 821 rounds to 800; 161 rounds to 200
- 800 − 200 = 600
The exact answer is 660, close to the estimate.
10.Estimate 39 × 7 by rounding 39 to the nearest 10.
Answer: 280
- 39 rounds to 40
- 40 × 7 = 280
The exact answer is 273.
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.