← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 826 · 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 593 + 180? (a) 600 (b) 800 (c) 1000
  2. 2.Best estimate of 752 + 870? (a) 1900 (b) 1700 (c) 1500
  3. 3.Best estimate of 879 + 538? (a) 1400 (b) 1600 (c) 1200
  4. 4.Best estimate of 663 + 127? (a) 1000 (b) 600 (c) 800
  5. 5.Best estimate of 87 × 84? (a) 72000 (b) 7200 (c) 720
  6. 6.Best estimate of 152 + 749? (a) 700 (b) 1100 (c) 900
  7. 7.Best estimate of 76 × 32? (a) 240 (b) 2400 (c) 24000
  8. 8.Best estimate of 13 × 17? (a) 20 (b) 200 (c) 2000
  9. 9.Best estimate of 62 × 23? (a) 1200 (b) 12000 (c) 120
  10. 10.Best estimate of 27 × 94? (a) 270 (b) 27000 (c) 2700
  11. 11.Best estimate of 12 × 63? (a) 600 (b) 6000 (c) 60
  12. 12.Best estimate of 56 × 13? (a) 600 (b) 6000 (c) 60
  13. 13.Best estimate of 87 × 73? (a) 63000 (b) 6300 (c) 630
  14. 14.Best estimate of 33 × 42? (a) 12000 (b) 1200 (c) 120
  15. 15.Best estimate of 52 × 17? (a) 10000 (b) 1000 (c) 100
  16. 16.Best estimate of 261 + 362? (a) 700 (b) 500 (c) 900
  17. 17.Best estimate of 492 + 738? (a) 1200 (b) 1000 (c) 1400
  18. 18.Best estimate of 66 × 88? (a) 63000 (b) 6300 (c) 630
  19. 19.Best estimate of 624 + 321? (a) 900 (b) 1100 (c) 700
  20. 20.Best estimate of 403 + 666? (a) 900 (b) 1300 (c) 1100
  21. 21.Best estimate of 853 + 381? (a) 1500 (b) 1100 (c) 1300
  22. 22.Best estimate of 64 × 76? (a) 4800 (b) 480 (c) 48000
  23. 23.Best estimate of 60 × 87? (a) 540 (b) 5400 (c) 54000
  24. 24.Best estimate of 72 × 86? (a) 63000 (b) 630 (c) 6300
  25. 25.Best estimate of 80 × 56? (a) 480 (b) 48000 (c) 4800
  26. 26.Best estimate of 34 × 69? (a) 21000 (b) 210 (c) 2100
  27. 27.Best estimate of 32 × 32? (a) 9000 (b) 900 (c) 90
  28. 28.Best estimate of 346 + 860? (a) 1400 (b) 1000 (c) 1200
  29. 29.Best estimate of 79 × 61? (a) 4800 (b) 480 (c) 48000
  30. 30.Best estimate of 749 + 434? (a) 1300 (b) 1100 (c) 900
  31. 31.Best estimate of 12 × 52? (a) 5000 (b) 500 (c) 50
  32. 32.Best estimate of 403 + 820? (a) 1000 (b) 1400 (c) 1200
  33. 33.Best estimate of 195 + 472? (a) 900 (b) 700 (c) 500
  34. 34.Best estimate of 778 + 574? (a) 1600 (b) 1200 (c) 1400
  35. 35.Best estimate of 60 × 91? (a) 540 (b) 54000 (c) 5400
  36. 36.Best estimate of 33 × 24? (a) 600 (b) 6000 (c) 60
  37. 37.Best estimate of 19 × 27? (a) 6000 (b) 60 (c) 600
  38. 38.Best estimate of 453 + 806? (a) 1500 (b) 1100 (c) 1300
  39. 39.Best estimate of 49 × 93? (a) 450 (b) 4500 (c) 45000
  40. 40.Best estimate of 91 × 34? (a) 270 (b) 27000 (c) 2700

Answer key

  1. 800
  2. 1700
  3. 1400
  4. 800
  5. 7200
  6. 900
  7. 2400
  8. 200
  9. 1200
  10. 2700
  11. 600
  12. 600
  13. 6300
  14. 1200
  15. 1000
  16. 700
  17. 1200
  18. 6300
  19. 900
  20. 1100
  21. 1300
  22. 4800
  23. 5400
  24. 6300
  25. 4800
  26. 2100
  27. 900
  28. 1200
  29. 4800
  30. 1100
  31. 500
  32. 1200
  33. 700
  34. 1400
  35. 5400
  36. 600
  37. 600
  38. 1300
  39. 4500
  40. 2700

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