← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 74 · 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 32 × 40? (a) 12000 (b) 1200 (c) 120
  2. 2.Best estimate of 153 + 628? (a) 1000 (b) 600 (c) 800
  3. 3.Best estimate of 702 + 839? (a) 1500 (b) 1700 (c) 1300
  4. 4.Best estimate of 98 × 38? (a) 4000 (b) 400 (c) 40000
  5. 5.Best estimate of 48 × 46? (a) 250 (b) 25000 (c) 2500
  6. 6.Best estimate of 46 × 62? (a) 3000 (b) 300 (c) 30000
  7. 7.Best estimate of 24 × 56? (a) 1200 (b) 120 (c) 12000
  8. 8.Best estimate of 76 × 46? (a) 400 (b) 40000 (c) 4000
  9. 9.Best estimate of 16 × 83? (a) 160 (b) 1600 (c) 16000
  10. 10.Best estimate of 56 × 39? (a) 240 (b) 24000 (c) 2400
  11. 11.Best estimate of 46 × 94? (a) 45000 (b) 4500 (c) 450
  12. 12.Best estimate of 88 × 62? (a) 540 (b) 5400 (c) 54000
  13. 13.Best estimate of 47 × 67? (a) 350 (b) 3500 (c) 35000
  14. 14.Best estimate of 751 + 288? (a) 900 (b) 1300 (c) 1100
  15. 15.Best estimate of 89 × 72? (a) 630 (b) 6300 (c) 63000
  16. 16.Best estimate of 76 × 83? (a) 6400 (b) 64000 (c) 640
  17. 17.Best estimate of 44 × 31? (a) 1200 (b) 120 (c) 12000
  18. 18.Best estimate of 26 × 59? (a) 180 (b) 1800 (c) 18000
  19. 19.Best estimate of 62 × 16? (a) 12000 (b) 1200 (c) 120
  20. 20.Best estimate of 23 × 87? (a) 1800 (b) 180 (c) 18000
  21. 21.Best estimate of 56 × 29? (a) 1800 (b) 18000 (c) 180
  22. 22.Best estimate of 817 + 777? (a) 1400 (b) 1600 (c) 1800
  23. 23.Best estimate of 264 + 686? (a) 800 (b) 1000 (c) 1200
  24. 24.Best estimate of 50 × 93? (a) 45000 (b) 4500 (c) 450
  25. 25.Best estimate of 813 + 477? (a) 1300 (b) 1500 (c) 1100
  26. 26.Best estimate of 161 + 129? (a) 100 (b) 300 (c) 500
  27. 27.Best estimate of 275 + 678? (a) 1000 (b) 1200 (c) 800
  28. 28.Best estimate of 89 × 38? (a) 360 (b) 36000 (c) 3600
  29. 29.Best estimate of 558 + 469? (a) 900 (b) 1300 (c) 1100
  30. 30.Best estimate of 339 + 472? (a) 600 (b) 1000 (c) 800
  31. 31.Best estimate of 668 + 537? (a) 1400 (b) 1000 (c) 1200
  32. 32.Best estimate of 730 + 600? (a) 1500 (b) 1100 (c) 1300
  33. 33.Best estimate of 751 + 661? (a) 1500 (b) 1300 (c) 1700
  34. 34.Best estimate of 302 + 257? (a) 600 (b) 400 (c) 800
  35. 35.Best estimate of 70 × 50? (a) 3500 (b) 35000 (c) 350
  36. 36.Best estimate of 81 × 20? (a) 1600 (b) 16000 (c) 160
  37. 37.Best estimate of 738 + 584? (a) 1300 (b) 1100 (c) 1500
  38. 38.Best estimate of 69 × 31? (a) 210 (b) 2100 (c) 21000
  39. 39.Best estimate of 547 + 363? (a) 700 (b) 1100 (c) 900
  40. 40.Best estimate of 33 × 20? (a) 6000 (b) 600 (c) 60

Answer key

  1. 1200
  2. 800
  3. 1500
  4. 4000
  5. 2500
  6. 3000
  7. 1200
  8. 4000
  9. 1600
  10. 2400
  11. 4500
  12. 5400
  13. 3500
  14. 1100
  15. 6300
  16. 6400
  17. 1200
  18. 1800
  19. 1200
  20. 1800
  21. 1800
  22. 1600
  23. 1000
  24. 4500
  25. 1300
  26. 300
  27. 1000
  28. 3600
  29. 1100
  30. 800
  31. 1200
  32. 1300
  33. 1500
  34. 600
  35. 3500
  36. 1600
  37. 1300
  38. 2100
  39. 900
  40. 600

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