Year 4 Estimating Sums, Differences and Products Worksheet — Level 3 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 4 place value worksheet.
Success TutoringWorksheetsAnswer sheetYear 4 · Mathematics · Place ValueYear 4 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 5,392 − 3,714 by rounding each number to the nearest 100.
Answer: 1,700
- 5,392 rounds to 5,400; 3,714 rounds to 3,700
- 5,400 − 3,700 = 1,700
The exact answer is 1,678, close to the estimate.
2.Estimate 14 × 27 by rounding each number to the nearest 10.
Answer: 300
- 14 rounds to 10; 27 rounds to 30
- 10 × 30 = 300
The exact answer is 378.
3.Estimate 18 × 78 by rounding each number to the nearest 10.
Answer: 1,600
- 18 rounds to 20; 78 rounds to 80
- 20 × 80 = 1,600
The exact answer is 1,404.
4.Estimate 3,025 − 2,002 by rounding each number to the nearest 1,000.
Answer: 1,000
- 3,025 rounds to 3,000; 2,002 rounds to 2,000
- 3,000 − 2,000 = 1,000
The exact answer is 1,023, close to the estimate.
5.Estimate 55 × 87 by rounding each number to the nearest 10.
Answer: 5,400
- 55 rounds to 60; 87 rounds to 90
- 60 × 90 = 5,400
The exact answer is 4,785.
6.Estimate 16 × 6 by rounding 16 to the nearest 10.
Answer: 120
- 16 rounds to 20
- 20 × 6 = 120
The exact answer is 96.
7.Estimate 7,451 + 3,929 by rounding each number to the nearest 100.
Answer: 11,400
- 7,451 rounds to 7,500; 3,929 rounds to 3,900
- 7,500 + 3,900 = 11,400
The exact answer is 11,380, close to the estimate.
8.Estimate 78 × 99 by rounding each number to the nearest 10.
Answer: 8,000
- 78 rounds to 80; 99 rounds to 100
- 80 × 100 = 8,000
The exact answer is 7,722.
9.Estimate 71 × 6 by rounding 71 to the nearest 10.
Answer: 420
- 71 rounds to 70
- 70 × 6 = 420
The exact answer is 426.
10.Estimate 5,977 + 3,989 by rounding each number to the nearest 1,000.
Answer: 10,000
- 5,977 rounds to 6,000; 3,989 rounds to 4,000
- 6,000 + 4,000 = 10,000
The exact answer is 9,966, 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.