← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 931 · 40 questions
TalentJR

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. 1.Best estimate of 66 × 86? (a) 630 (b) 63000 (c) 6300
  2. 2.Best estimate of 463 + 472? (a) 800 (b) 1200 (c) 1000
  3. 3.Best estimate of 20 × 27? (a) 600 (b) 6000 (c) 60
  4. 4.Best estimate of 859 + 664? (a) 1400 (b) 1600 (c) 1800
  5. 5.Best estimate of 486 + 475? (a) 1200 (b) 800 (c) 1000
  6. 6.Best estimate of 21 × 60? (a) 120 (b) 1200 (c) 12000
  7. 7.Best estimate of 36 × 56? (a) 24000 (b) 2400 (c) 240
  8. 8.Best estimate of 70 × 38? (a) 28000 (b) 280 (c) 2800
  9. 9.Best estimate of 31 × 36? (a) 12000 (b) 120 (c) 1200
  10. 10.Best estimate of 571 + 182? (a) 1000 (b) 600 (c) 800
  11. 11.Best estimate of 93 × 57? (a) 54000 (b) 5400 (c) 540
  12. 12.Best estimate of 240 + 131? (a) 300 (b) 100 (c) 500
  13. 13.Best estimate of 58 × 44? (a) 240 (b) 2400 (c) 24000
  14. 14.Best estimate of 18 × 76? (a) 16000 (b) 1600 (c) 160
  15. 15.Best estimate of 347 + 871? (a) 1400 (b) 1000 (c) 1200
  16. 16.Best estimate of 84 × 19? (a) 160 (b) 1600 (c) 16000
  17. 17.Best estimate of 514 + 795? (a) 1300 (b) 1100 (c) 1500
  18. 18.Best estimate of 66 × 74? (a) 4900 (b) 49000 (c) 490
  19. 19.Best estimate of 54 × 51? (a) 2500 (b) 250 (c) 25000
  20. 20.Best estimate of 61 × 63? (a) 36000 (b) 360 (c) 3600
  21. 21.Best estimate of 400 + 610? (a) 1200 (b) 800 (c) 1000
  22. 22.Best estimate of 297 + 729? (a) 1000 (b) 800 (c) 1200
  23. 23.Best estimate of 193 + 652? (a) 1100 (b) 900 (c) 700
  24. 24.Best estimate of 69 × 59? (a) 42000 (b) 4200 (c) 420
  25. 25.Best estimate of 848 + 576? (a) 1600 (b) 1400 (c) 1200
  26. 26.Best estimate of 324 + 796? (a) 1100 (b) 1300 (c) 900
  27. 27.Best estimate of 17 × 58? (a) 12000 (b) 120 (c) 1200
  28. 28.Best estimate of 97 × 72? (a) 7000 (b) 700 (c) 70000
  29. 29.Best estimate of 555 + 339? (a) 1100 (b) 700 (c) 900
  30. 30.Best estimate of 254 + 486? (a) 800 (b) 600 (c) 1000
  31. 31.Best estimate of 475 + 844? (a) 1100 (b) 1300 (c) 1500
  32. 32.Best estimate of 22 × 28? (a) 6000 (b) 60 (c) 600
  33. 33.Best estimate of 665 + 439? (a) 1300 (b) 1100 (c) 900
  34. 34.Best estimate of 18 × 24? (a) 4000 (b) 40 (c) 400
  35. 35.Best estimate of 58 × 48? (a) 3000 (b) 300 (c) 30000
  36. 36.Best estimate of 81 × 36? (a) 32000 (b) 3200 (c) 320
  37. 37.Best estimate of 572 + 782? (a) 1600 (b) 1200 (c) 1400
  38. 38.Best estimate of 152 + 197? (a) 400 (b) 200 (c) 600
  39. 39.Best estimate of 651 + 689? (a) 1200 (b) 1600 (c) 1400
  40. 40.Best estimate of 828 + 393? (a) 1400 (b) 1000 (c) 1200

Answer key

  1. 6300
  2. 1000
  3. 600
  4. 1600
  5. 1000
  6. 1200
  7. 2400
  8. 2800
  9. 1200
  10. 800
  11. 5400
  12. 300
  13. 2400
  14. 1600
  15. 1200
  16. 1600
  17. 1300
  18. 4900
  19. 2500
  20. 3600
  21. 1000
  22. 1000
  23. 900
  24. 4200
  25. 1400
  26. 1100
  27. 1200
  28. 7000
  29. 900
  30. 800
  31. 1300
  32. 600
  33. 1100
  34. 400
  35. 3000
  36. 3200
  37. 1400
  38. 400
  39. 1400
  40. 1200

Free mental maths lessons, practice and worksheets at talentjr.in/mental-maths