← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 945 · 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 457 + 836? (a) 1300 (b) 1500 (c) 1100
  2. 2.Best estimate of 17 × 13? (a) 2000 (b) 20 (c) 200
  3. 3.Best estimate of 88 × 77? (a) 7200 (b) 72000 (c) 720
  4. 4.Best estimate of 33 × 94? (a) 27000 (b) 270 (c) 2700
  5. 5.Best estimate of 780 + 814? (a) 1800 (b) 1400 (c) 1600
  6. 6.Best estimate of 27 × 21? (a) 6000 (b) 600 (c) 60
  7. 7.Best estimate of 455 + 465? (a) 800 (b) 1200 (c) 1000
  8. 8.Best estimate of 767 + 541? (a) 1500 (b) 1300 (c) 1100
  9. 9.Best estimate of 60 × 32? (a) 18000 (b) 1800 (c) 180
  10. 10.Best estimate of 47 × 31? (a) 1500 (b) 15000 (c) 150
  11. 11.Best estimate of 152 + 637? (a) 600 (b) 1000 (c) 800
  12. 12.Best estimate of 724 + 162? (a) 1100 (b) 700 (c) 900
  13. 13.Best estimate of 97 × 66? (a) 70000 (b) 7000 (c) 700
  14. 14.Best estimate of 51 × 17? (a) 1000 (b) 100 (c) 10000
  15. 15.Best estimate of 817 + 378? (a) 1200 (b) 1400 (c) 1000
  16. 16.Best estimate of 796 + 284? (a) 1300 (b) 900 (c) 1100
  17. 17.Best estimate of 96 × 91? (a) 9000 (b) 90000 (c) 900
  18. 18.Best estimate of 394 + 335? (a) 900 (b) 500 (c) 700
  19. 19.Best estimate of 278 + 659? (a) 1200 (b) 1000 (c) 800
  20. 20.Best estimate of 445 + 617? (a) 1000 (b) 1200 (c) 800
  21. 21.Best estimate of 633 + 642? (a) 1200 (b) 1000 (c) 1400
  22. 22.Best estimate of 471 + 295? (a) 800 (b) 1000 (c) 600
  23. 23.Best estimate of 616 + 376? (a) 1000 (b) 800 (c) 1200
  24. 24.Best estimate of 56 × 60? (a) 360 (b) 3600 (c) 36000
  25. 25.Best estimate of 406 + 761? (a) 1200 (b) 1000 (c) 1400
  26. 26.Best estimate of 347 + 142? (a) 200 (b) 600 (c) 400
  27. 27.Best estimate of 461 + 413? (a) 900 (b) 1100 (c) 700
  28. 28.Best estimate of 39 × 77? (a) 3200 (b) 32000 (c) 320
  29. 29.Best estimate of 94 × 97? (a) 90000 (b) 900 (c) 9000
  30. 30.Best estimate of 41 × 63? (a) 24000 (b) 240 (c) 2400
  31. 31.Best estimate of 36 × 61? (a) 24000 (b) 240 (c) 2400
  32. 32.Best estimate of 30 × 39? (a) 120 (b) 1200 (c) 12000
  33. 33.Best estimate of 872 + 758? (a) 1500 (b) 1700 (c) 1900
  34. 34.Best estimate of 30 × 29? (a) 90 (b) 900 (c) 9000
  35. 35.Best estimate of 57 × 14? (a) 6000 (b) 600 (c) 60
  36. 36.Best estimate of 54 × 41? (a) 2000 (b) 200 (c) 20000
  37. 37.Best estimate of 36 × 77? (a) 320 (b) 3200 (c) 32000
  38. 38.Best estimate of 784 + 208? (a) 800 (b) 1200 (c) 1000
  39. 39.Best estimate of 36 × 24? (a) 800 (b) 80 (c) 8000
  40. 40.Best estimate of 56 × 40? (a) 240 (b) 24000 (c) 2400

Answer key

  1. 1300
  2. 200
  3. 7200
  4. 2700
  5. 1600
  6. 600
  7. 1000
  8. 1300
  9. 1800
  10. 1500
  11. 800
  12. 900
  13. 7000
  14. 1000
  15. 1200
  16. 1100
  17. 9000
  18. 700
  19. 1000
  20. 1000
  21. 1200
  22. 800
  23. 1000
  24. 3600
  25. 1200
  26. 400
  27. 900
  28. 3200
  29. 9000
  30. 2400
  31. 2400
  32. 1200
  33. 1700
  34. 900
  35. 600
  36. 2000
  37. 3200
  38. 1000
  39. 800
  40. 2400

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