← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 534 · 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 566 + 739? (a) 1300 (b) 1100 (c) 1500
  2. 2.Best estimate of 543 + 514? (a) 1000 (b) 1200 (c) 800
  3. 3.Best estimate of 496 + 369? (a) 900 (b) 700 (c) 1100
  4. 4.Best estimate of 56 × 29? (a) 1800 (b) 18000 (c) 180
  5. 5.Best estimate of 27 × 71? (a) 2100 (b) 210 (c) 21000
  6. 6.Best estimate of 24 × 64? (a) 12000 (b) 120 (c) 1200
  7. 7.Best estimate of 92 × 17? (a) 18000 (b) 180 (c) 1800
  8. 8.Best estimate of 26 × 26? (a) 9000 (b) 900 (c) 90
  9. 9.Best estimate of 68 × 71? (a) 49000 (b) 490 (c) 4900
  10. 10.Best estimate of 67 × 78? (a) 560 (b) 56000 (c) 5600
  11. 11.Best estimate of 478 + 857? (a) 1600 (b) 1400 (c) 1200
  12. 12.Best estimate of 60 × 36? (a) 24000 (b) 2400 (c) 240
  13. 13.Best estimate of 569 + 386? (a) 1000 (b) 800 (c) 1200
  14. 14.Best estimate of 848 + 721? (a) 1700 (b) 1500 (c) 1300
  15. 15.Best estimate of 180 + 872? (a) 1300 (b) 1100 (c) 900
  16. 16.Best estimate of 516 + 581? (a) 900 (b) 1100 (c) 1300
  17. 17.Best estimate of 351 + 694? (a) 1300 (b) 1100 (c) 900
  18. 18.Best estimate of 268 + 467? (a) 800 (b) 600 (c) 1000
  19. 19.Best estimate of 316 + 834? (a) 1300 (b) 900 (c) 1100
  20. 20.Best estimate of 13 × 86? (a) 9000 (b) 900 (c) 90
  21. 21.Best estimate of 42 × 66? (a) 2800 (b) 280 (c) 28000
  22. 22.Best estimate of 423 + 606? (a) 1200 (b) 1000 (c) 800
  23. 23.Best estimate of 635 + 718? (a) 1500 (b) 1100 (c) 1300
  24. 24.Best estimate of 16 × 70? (a) 140 (b) 1400 (c) 14000
  25. 25.Best estimate of 47 × 33? (a) 1500 (b) 150 (c) 15000
  26. 26.Best estimate of 616 + 514? (a) 900 (b) 1100 (c) 1300
  27. 27.Best estimate of 96 × 26? (a) 300 (b) 3000 (c) 30000
  28. 28.Best estimate of 328 + 566? (a) 1100 (b) 900 (c) 700
  29. 29.Best estimate of 14 × 66? (a) 7000 (b) 70 (c) 700
  30. 30.Best estimate of 74 × 51? (a) 3500 (b) 35000 (c) 350
  31. 31.Best estimate of 90 × 43? (a) 3600 (b) 36000 (c) 360
  32. 32.Best estimate of 370 + 835? (a) 1400 (b) 1200 (c) 1000
  33. 33.Best estimate of 14 × 21? (a) 200 (b) 20 (c) 2000
  34. 34.Best estimate of 98 × 96? (a) 1000 (b) 10000 (c) 100000
  35. 35.Best estimate of 26 × 61? (a) 1800 (b) 180 (c) 18000
  36. 36.Best estimate of 66 × 13? (a) 7000 (b) 700 (c) 70
  37. 37.Best estimate of 226 + 860? (a) 1100 (b) 900 (c) 1300
  38. 38.Best estimate of 46 × 90? (a) 45000 (b) 4500 (c) 450
  39. 39.Best estimate of 16 × 27? (a) 6000 (b) 600 (c) 60
  40. 40.Best estimate of 29 × 12? (a) 3000 (b) 300 (c) 30

Answer key

  1. 1300
  2. 1000
  3. 900
  4. 1800
  5. 2100
  6. 1200
  7. 1800
  8. 900
  9. 4900
  10. 5600
  11. 1400
  12. 2400
  13. 1000
  14. 1500
  15. 1100
  16. 1100
  17. 1100
  18. 800
  19. 1100
  20. 900
  21. 2800
  22. 1000
  23. 1300
  24. 1400
  25. 1500
  26. 1100
  27. 3000
  28. 900
  29. 700
  30. 3500
  31. 3600
  32. 1200
  33. 200
  34. 10000
  35. 1800
  36. 700
  37. 1100
  38. 4500
  39. 600
  40. 300

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