← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 514 · 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 48 × 84? (a) 400 (b) 40000 (c) 4000
  2. 2.Best estimate of 269 + 254? (a) 800 (b) 600 (c) 400
  3. 3.Best estimate of 413 + 262? (a) 900 (b) 700 (c) 500
  4. 4.Best estimate of 13 × 89? (a) 90 (b) 9000 (c) 900
  5. 5.Best estimate of 24 × 66? (a) 1400 (b) 14000 (c) 140
  6. 6.Best estimate of 62 × 12? (a) 600 (b) 60 (c) 6000
  7. 7.Best estimate of 86 × 86? (a) 8100 (b) 81000 (c) 810
  8. 8.Best estimate of 46 × 19? (a) 100 (b) 10000 (c) 1000
  9. 9.Best estimate of 59 × 84? (a) 480 (b) 4800 (c) 48000
  10. 10.Best estimate of 797 + 139? (a) 900 (b) 1100 (c) 700
  11. 11.Best estimate of 69 × 16? (a) 14000 (b) 1400 (c) 140
  12. 12.Best estimate of 408 + 355? (a) 1000 (b) 600 (c) 800
  13. 13.Best estimate of 56 × 28? (a) 18000 (b) 1800 (c) 180
  14. 14.Best estimate of 155 + 500? (a) 900 (b) 500 (c) 700
  15. 15.Best estimate of 44 × 57? (a) 240 (b) 24000 (c) 2400
  16. 16.Best estimate of 16 × 31? (a) 6000 (b) 600 (c) 60
  17. 17.Best estimate of 91 × 50? (a) 450 (b) 4500 (c) 45000
  18. 18.Best estimate of 435 + 630? (a) 1000 (b) 800 (c) 1200
  19. 19.Best estimate of 241 + 529? (a) 700 (b) 900 (c) 500
  20. 20.Best estimate of 88 × 21? (a) 180 (b) 1800 (c) 18000
  21. 21.Best estimate of 196 + 476? (a) 900 (b) 500 (c) 700
  22. 22.Best estimate of 690 + 659? (a) 1200 (b) 1400 (c) 1600
  23. 23.Best estimate of 652 + 752? (a) 1500 (b) 1700 (c) 1300
  24. 24.Best estimate of 730 + 323? (a) 800 (b) 1000 (c) 1200
  25. 25.Best estimate of 331 + 281? (a) 600 (b) 400 (c) 800
  26. 26.Best estimate of 483 + 128? (a) 600 (b) 800 (c) 400
  27. 27.Best estimate of 656 + 467? (a) 1200 (b) 1000 (c) 1400
  28. 28.Best estimate of 643 + 198? (a) 1000 (b) 600 (c) 800
  29. 29.Best estimate of 634 + 222? (a) 1000 (b) 600 (c) 800
  30. 30.Best estimate of 19 × 47? (a) 1000 (b) 10000 (c) 100
  31. 31.Best estimate of 92 × 28? (a) 27000 (b) 270 (c) 2700
  32. 32.Best estimate of 74 × 62? (a) 420 (b) 42000 (c) 4200
  33. 33.Best estimate of 13 × 23? (a) 2000 (b) 20 (c) 200
  34. 34.Best estimate of 192 + 212? (a) 200 (b) 600 (c) 400
  35. 35.Best estimate of 23 × 56? (a) 1200 (b) 120 (c) 12000
  36. 36.Best estimate of 295 + 717? (a) 1200 (b) 1000 (c) 800
  37. 37.Best estimate of 260 + 511? (a) 1000 (b) 600 (c) 800
  38. 38.Best estimate of 230 + 698? (a) 1100 (b) 700 (c) 900
  39. 39.Best estimate of 611 + 864? (a) 1300 (b) 1700 (c) 1500
  40. 40.Best estimate of 96 × 24? (a) 200 (b) 20000 (c) 2000

Answer key

  1. 4000
  2. 600
  3. 700
  4. 900
  5. 1400
  6. 600
  7. 8100
  8. 1000
  9. 4800
  10. 900
  11. 1400
  12. 800
  13. 1800
  14. 700
  15. 2400
  16. 600
  17. 4500
  18. 1000
  19. 700
  20. 1800
  21. 700
  22. 1400
  23. 1500
  24. 1000
  25. 600
  26. 600
  27. 1200
  28. 800
  29. 800
  30. 1000
  31. 2700
  32. 4200
  33. 200
  34. 400
  35. 1200
  36. 1000
  37. 800
  38. 900
  39. 1500
  40. 2000

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