3rd Grade Estimating Sums, Differences and Products Worksheet — Level 3 — Practice Set 2 — 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 2 — Answers
Round each number first, then work out the estimate in your head.
1.Estimate 6,161 + 9,869 by rounding each number to the nearest 100.
Answer: 16,100
- 6,161 rounds to 6,200; 9,869 rounds to 9,900
- 6,200 + 9,900 = 16,100
The exact answer is 16,030, close to the estimate.
2.Estimate 77 × 55 by rounding each number to the nearest 10.
Answer: 4,800
- 77 rounds to 80; 55 rounds to 60
- 80 × 60 = 4,800
The exact answer is 4,235.
3.Estimate 14 × 9 by rounding 14 to the nearest 10.
Answer: 90
- 14 rounds to 10
- 10 × 9 = 90
The exact answer is 126.
4.Estimate 8,643 + 1,155 by rounding each number to the nearest 1,000.
Answer: 10,000
- 8,643 rounds to 9,000; 1,155 rounds to 1,000
- 9,000 + 1,000 = 10,000
The exact answer is 9,798, close to the estimate.
5.Estimate 44 × 85 by rounding each number to the nearest 10.
Answer: 3,600
- 44 rounds to 40; 85 rounds to 90
- 40 × 90 = 3,600
The exact answer is 3,740.
6.Estimate 25 × 47 by rounding each number to the nearest 10.
Answer: 1,500
- 25 rounds to 30; 47 rounds to 50
- 30 × 50 = 1,500
The exact answer is 1,175.
7.Estimate 2,572 + 8,298 by rounding each number to the nearest 100.
Answer: 10,900
- 2,572 rounds to 2,600; 8,298 rounds to 8,300
- 2,600 + 8,300 = 10,900
The exact answer is 10,870, close to the estimate.
8.Estimate 16 × 95 by rounding each number to the nearest 10.
Answer: 2,000
- 16 rounds to 20; 95 rounds to 100
- 20 × 100 = 2,000
The exact answer is 1,520.
9.Estimate 58 × 57 by rounding each number to the nearest 10.
Answer: 3,600
- 58 rounds to 60; 57 rounds to 60
- 60 × 60 = 3,600
The exact answer is 3,306.
10.Estimate 7,425 − 5,451 by rounding each number to the nearest 100.
Answer: 1,900
- 7,425 rounds to 7,400; 5,451 rounds to 5,500
- 7,400 − 5,500 = 1,900
The exact answer is 1,974, 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.