3rd Grade Estimating Sums, Differences and Products Worksheet — Level 2 — 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 2 — Practice Set 3 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 322 + 319 by rounding each number to the nearest 100.
Answer: 600
- 322 rounds to 300; 319 rounds to 300
- 300 + 300 = 600
The exact answer is 641, close to the estimate.
2.Estimate 88 × 8 by rounding 88 to the nearest 10.
Answer: 720
- 88 rounds to 90
- 90 × 8 = 720
The exact answer is 704.
3.Estimate 853 + 397 by rounding each number to the nearest 100.
Answer: 1,300
- 853 rounds to 900; 397 rounds to 400
- 900 + 400 = 1,300
The exact answer is 1,250, close to the estimate.
4.Estimate 26 × 8 by rounding 26 to the nearest 10.
Answer: 240
- 26 rounds to 30
- 30 × 8 = 240
The exact answer is 208.
5.Estimate 593 + 254 by rounding each number to the nearest 100.
Answer: 900
- 593 rounds to 600; 254 rounds to 300
- 600 + 300 = 900
The exact answer is 847, close to the estimate.
6.Estimate 93 × 6 by rounding 93 to the nearest 10.
Answer: 540
- 93 rounds to 90
- 90 × 6 = 540
The exact answer is 558.
7.Estimate 668 − 380 by rounding each number to the nearest 100.
Answer: 300
- 668 rounds to 700; 380 rounds to 400
- 700 − 400 = 300
The exact answer is 288, close to the estimate.
8.Estimate 96 × 4 by rounding 96 to the nearest 10.
Answer: 400
- 96 rounds to 100
- 100 × 4 = 400
The exact answer is 384.
9.Estimate 353 + 446 by rounding each number to the nearest 100.
Answer: 800
- 353 rounds to 400; 446 rounds to 400
- 400 + 400 = 800
The exact answer is 799, close to the estimate.
10.Estimate 41 × 8 by rounding 41 to the nearest 10.
Answer: 320
- 41 rounds to 40
- 40 × 8 = 320
The exact answer is 328.
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.