← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 697 · 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 722 + 373? (a) 1300 (b) 900 (c) 1100
  2. 2.Best estimate of 163 + 832? (a) 1200 (b) 1000 (c) 800
  3. 3.Best estimate of 688 + 449? (a) 900 (b) 1100 (c) 1300
  4. 4.Best estimate of 96 × 31? (a) 3000 (b) 300 (c) 30000
  5. 5.Best estimate of 179 + 772? (a) 1200 (b) 800 (c) 1000
  6. 6.Best estimate of 554 + 797? (a) 1200 (b) 1400 (c) 1600
  7. 7.Best estimate of 238 + 258? (a) 700 (b) 500 (c) 300
  8. 8.Best estimate of 73 × 42? (a) 28000 (b) 280 (c) 2800
  9. 9.Best estimate of 52 × 66? (a) 350 (b) 3500 (c) 35000
  10. 10.Best estimate of 23 × 22? (a) 400 (b) 4000 (c) 40
  11. 11.Best estimate of 409 + 320? (a) 500 (b) 900 (c) 700
  12. 12.Best estimate of 140 + 748? (a) 800 (b) 600 (c) 1000
  13. 13.Best estimate of 372 + 221? (a) 600 (b) 400 (c) 800
  14. 14.Best estimate of 641 + 679? (a) 1300 (b) 1500 (c) 1100
  15. 15.Best estimate of 283 + 609? (a) 700 (b) 900 (c) 1100
  16. 16.Best estimate of 77 × 33? (a) 2400 (b) 24000 (c) 240
  17. 17.Best estimate of 536 + 687? (a) 1400 (b) 1200 (c) 1000
  18. 18.Best estimate of 98 × 77? (a) 800 (b) 8000 (c) 80000
  19. 19.Best estimate of 98 × 56? (a) 60000 (b) 600 (c) 6000
  20. 20.Best estimate of 657 + 454? (a) 1000 (b) 1200 (c) 1400
  21. 21.Best estimate of 745 + 646? (a) 1500 (b) 1300 (c) 1100
  22. 22.Best estimate of 564 + 349? (a) 900 (b) 700 (c) 1100
  23. 23.Best estimate of 193 + 549? (a) 900 (b) 500 (c) 700
  24. 24.Best estimate of 19 × 76? (a) 160 (b) 16000 (c) 1600
  25. 25.Best estimate of 82 × 32? (a) 240 (b) 2400 (c) 24000
  26. 26.Best estimate of 174 + 277? (a) 700 (b) 500 (c) 300
  27. 27.Best estimate of 27 × 84? (a) 2400 (b) 24000 (c) 240
  28. 28.Best estimate of 842 + 660? (a) 1700 (b) 1300 (c) 1500
  29. 29.Best estimate of 44 × 91? (a) 360 (b) 3600 (c) 36000
  30. 30.Best estimate of 616 + 132? (a) 900 (b) 500 (c) 700
  31. 31.Best estimate of 51 × 18? (a) 1000 (b) 10000 (c) 100
  32. 32.Best estimate of 18 × 52? (a) 10000 (b) 1000 (c) 100
  33. 33.Best estimate of 33 × 76? (a) 2400 (b) 240 (c) 24000
  34. 34.Best estimate of 69 × 32? (a) 2100 (b) 21000 (c) 210
  35. 35.Best estimate of 682 + 848? (a) 1500 (b) 1700 (c) 1300
  36. 36.Best estimate of 23 × 41? (a) 800 (b) 80 (c) 8000
  37. 37.Best estimate of 92 × 94? (a) 810 (b) 81000 (c) 8100
  38. 38.Best estimate of 67 × 34? (a) 2100 (b) 210 (c) 21000
  39. 39.Best estimate of 709 + 298? (a) 1000 (b) 800 (c) 1200
  40. 40.Best estimate of 87 × 12? (a) 9000 (b) 90 (c) 900

Answer key

  1. 1100
  2. 1000
  3. 1100
  4. 3000
  5. 1000
  6. 1400
  7. 500
  8. 2800
  9. 3500
  10. 400
  11. 700
  12. 800
  13. 600
  14. 1300
  15. 900
  16. 2400
  17. 1200
  18. 8000
  19. 6000
  20. 1200
  21. 1300
  22. 900
  23. 700
  24. 1600
  25. 2400
  26. 500
  27. 2400
  28. 1500
  29. 3600
  30. 700
  31. 1000
  32. 1000
  33. 2400
  34. 2100
  35. 1500
  36. 800
  37. 8100
  38. 2100
  39. 1000
  40. 900

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