Rounding Off and Estimation Worksheet
How to do it in your head (Round, then work): Round each number: 2-digit numbers to the nearest ten, 3-digit numbers to the nearest hundred. Do the easy sum with the round numbers. Choose the option closest to your estimate.
NameDateTime takenScore ___ / 40
- 1.Best estimate of 562 + 583? (a) 1200 (b) 1400 (c) 1000
- 2.Best estimate of 337 + 782? (a) 900 (b) 1300 (c) 1100
- 3.Best estimate of 329 + 834? (a) 900 (b) 1100 (c) 1300
- 4.Best estimate of 76 × 60? (a) 4800 (b) 480 (c) 48000
- 5.Best estimate of 96 × 86? (a) 900 (b) 9000 (c) 90000
- 6.Best estimate of 87 × 16? (a) 18000 (b) 1800 (c) 180
- 7.Best estimate of 73 × 89? (a) 63000 (b) 6300 (c) 630
- 8.Best estimate of 552 + 716? (a) 1100 (b) 1300 (c) 1500
- 9.Best estimate of 41 × 56? (a) 240 (b) 24000 (c) 2400
- 10.Best estimate of 82 × 26? (a) 2400 (b) 24000 (c) 240
- 11.Best estimate of 874 + 576? (a) 1500 (b) 1300 (c) 1700
- 12.Best estimate of 79 × 46? (a) 40000 (b) 4000 (c) 400
- 13.Best estimate of 549 + 406? (a) 1100 (b) 900 (c) 700
- 14.Best estimate of 26 × 23? (a) 600 (b) 6000 (c) 60
- 15.Best estimate of 782 + 470? (a) 1500 (b) 1300 (c) 1100
- 16.Best estimate of 715 + 464? (a) 1400 (b) 1000 (c) 1200
- 17.Best estimate of 283 + 459? (a) 800 (b) 1000 (c) 600
- 18.Best estimate of 455 + 436? (a) 900 (b) 1100 (c) 700
- 19.Best estimate of 33 × 77? (a) 2400 (b) 24000 (c) 240
- 20.Best estimate of 497 + 384? (a) 700 (b) 900 (c) 1100
- 21.Best estimate of 718 + 383? (a) 1300 (b) 1100 (c) 900
- 22.Best estimate of 56 × 61? (a) 36000 (b) 360 (c) 3600
- 23.Best estimate of 488 + 353? (a) 700 (b) 900 (c) 1100
- 24.Best estimate of 210 + 751? (a) 1200 (b) 1000 (c) 800
- 25.Best estimate of 76 × 36? (a) 32000 (b) 320 (c) 3200
- 26.Best estimate of 42 × 41? (a) 160 (b) 1600 (c) 16000
- 27.Best estimate of 82 × 91? (a) 72000 (b) 720 (c) 7200
- 28.Best estimate of 93 × 37? (a) 36000 (b) 360 (c) 3600
- 29.Best estimate of 66 × 62? (a) 420 (b) 4200 (c) 42000
- 30.Best estimate of 64 × 93? (a) 540 (b) 5400 (c) 54000
- 31.Best estimate of 175 + 783? (a) 1200 (b) 1000 (c) 800
- 32.Best estimate of 34 × 84? (a) 24000 (b) 240 (c) 2400
- 33.Best estimate of 36 × 23? (a) 80 (b) 800 (c) 8000
- 34.Best estimate of 29 × 58? (a) 1800 (b) 180 (c) 18000
- 35.Best estimate of 147 + 309? (a) 600 (b) 400 (c) 200
- 36.Best estimate of 52 × 96? (a) 5000 (b) 50000 (c) 500
- 37.Best estimate of 69 × 90? (a) 63000 (b) 6300 (c) 630
- 38.Best estimate of 52 × 74? (a) 3500 (b) 350 (c) 35000
- 39.Best estimate of 743 + 502? (a) 1400 (b) 1000 (c) 1200
- 40.Best estimate of 24 × 73? (a) 140 (b) 1400 (c) 14000
Answer key
- 1200
- 1100
- 1100
- 4800
- 9000
- 1800
- 6300
- 1300
- 2400
- 2400
- 1500
- 4000
- 900
- 600
- 1300
- 1200
- 800
- 900
- 2400
- 900
- 1100
- 3600
- 900
- 1000
- 3200
- 1600
- 7200
- 3600
- 4200
- 5400
- 1000
- 2400
- 800
- 1800
- 400
- 5000
- 6300
- 3500
- 1200
- 1400
Free mental maths lessons, practice and worksheets at talentjr.in/mental-maths