← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 927 · 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 426 + 579? (a) 1000 (b) 1200 (c) 800
  2. 2.Best estimate of 46 × 64? (a) 30000 (b) 300 (c) 3000
  3. 3.Best estimate of 282 + 809? (a) 900 (b) 1300 (c) 1100
  4. 4.Best estimate of 57 × 38? (a) 24000 (b) 240 (c) 2400
  5. 5.Best estimate of 508 + 179? (a) 700 (b) 900 (c) 500
  6. 6.Best estimate of 62 × 36? (a) 2400 (b) 24000 (c) 240
  7. 7.Best estimate of 23 × 88? (a) 180 (b) 18000 (c) 1800
  8. 8.Best estimate of 269 + 621? (a) 700 (b) 1100 (c) 900
  9. 9.Best estimate of 96 × 59? (a) 600 (b) 6000 (c) 60000
  10. 10.Best estimate of 27 × 88? (a) 2700 (b) 27000 (c) 270
  11. 11.Best estimate of 865 + 227? (a) 900 (b) 1100 (c) 1300
  12. 12.Best estimate of 22 × 22? (a) 4000 (b) 40 (c) 400
  13. 13.Best estimate of 76 × 28? (a) 24000 (b) 2400 (c) 240
  14. 14.Best estimate of 541 + 153? (a) 900 (b) 700 (c) 500
  15. 15.Best estimate of 722 + 767? (a) 1700 (b) 1500 (c) 1300
  16. 16.Best estimate of 74 × 56? (a) 42000 (b) 4200 (c) 420
  17. 17.Best estimate of 23 × 27? (a) 6000 (b) 600 (c) 60
  18. 18.Best estimate of 60 × 42? (a) 24000 (b) 240 (c) 2400
  19. 19.Best estimate of 89 × 61? (a) 5400 (b) 540 (c) 54000
  20. 20.Best estimate of 284 + 610? (a) 700 (b) 1100 (c) 900
  21. 21.Best estimate of 501 + 842? (a) 1300 (b) 1500 (c) 1100
  22. 22.Best estimate of 804 + 137? (a) 700 (b) 900 (c) 1100
  23. 23.Best estimate of 38 × 13? (a) 4000 (b) 400 (c) 40
  24. 24.Best estimate of 220 + 206? (a) 600 (b) 200 (c) 400
  25. 25.Best estimate of 186 + 420? (a) 400 (b) 800 (c) 600
  26. 26.Best estimate of 19 × 13? (a) 2000 (b) 20 (c) 200
  27. 27.Best estimate of 505 + 364? (a) 900 (b) 700 (c) 1100
  28. 28.Best estimate of 63 × 63? (a) 36000 (b) 360 (c) 3600
  29. 29.Best estimate of 728 + 542? (a) 1400 (b) 1200 (c) 1000
  30. 30.Best estimate of 284 + 343? (a) 600 (b) 400 (c) 800
  31. 31.Best estimate of 80 × 64? (a) 480 (b) 4800 (c) 48000
  32. 32.Best estimate of 16 × 50? (a) 1000 (b) 10000 (c) 100
  33. 33.Best estimate of 420 + 145? (a) 500 (b) 300 (c) 700
  34. 34.Best estimate of 34 × 77? (a) 2400 (b) 240 (c) 24000
  35. 35.Best estimate of 500 + 617? (a) 1300 (b) 1100 (c) 900
  36. 36.Best estimate of 523 + 675? (a) 1400 (b) 1000 (c) 1200
  37. 37.Best estimate of 69 × 86? (a) 630 (b) 63000 (c) 6300
  38. 38.Best estimate of 68 × 52? (a) 35000 (b) 3500 (c) 350
  39. 39.Best estimate of 767 + 616? (a) 1400 (b) 1600 (c) 1200
  40. 40.Best estimate of 540 + 844? (a) 1500 (b) 1100 (c) 1300

Answer key

  1. 1000
  2. 3000
  3. 1100
  4. 2400
  5. 700
  6. 2400
  7. 1800
  8. 900
  9. 6000
  10. 2700
  11. 1100
  12. 400
  13. 2400
  14. 700
  15. 1500
  16. 4200
  17. 600
  18. 2400
  19. 5400
  20. 900
  21. 1300
  22. 900
  23. 400
  24. 400
  25. 600
  26. 200
  27. 900
  28. 3600
  29. 1200
  30. 600
  31. 4800
  32. 1000
  33. 500
  34. 2400
  35. 1100
  36. 1200
  37. 6300
  38. 3500
  39. 1400
  40. 1300

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