← Rounding off and best estimate lesson New set →

Rounding Off and Estimation Worksheet

Mental maths lesson 15: Rounding off and best estimate · Set 269 · 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 534 + 722? (a) 1200 (b) 1000 (c) 1400
  2. 2.Best estimate of 63 × 39? (a) 2400 (b) 240 (c) 24000
  3. 3.Best estimate of 865 + 180? (a) 1100 (b) 1300 (c) 900
  4. 4.Best estimate of 840 + 637? (a) 1600 (b) 1400 (c) 1200
  5. 5.Best estimate of 427 + 678? (a) 1100 (b) 900 (c) 1300
  6. 6.Best estimate of 261 + 874? (a) 1200 (b) 1400 (c) 1000
  7. 7.Best estimate of 24 × 88? (a) 180 (b) 18000 (c) 1800
  8. 8.Best estimate of 175 + 218? (a) 200 (b) 600 (c) 400
  9. 9.Best estimate of 610 + 806? (a) 1600 (b) 1400 (c) 1200
  10. 10.Best estimate of 30 × 84? (a) 24000 (b) 240 (c) 2400
  11. 11.Best estimate of 48 × 86? (a) 45000 (b) 4500 (c) 450
  12. 12.Best estimate of 66 × 30? (a) 210 (b) 2100 (c) 21000
  13. 13.Best estimate of 26 × 16? (a) 6000 (b) 60 (c) 600
  14. 14.Best estimate of 880 + 698? (a) 1600 (b) 1800 (c) 1400
  15. 15.Best estimate of 84 × 49? (a) 4000 (b) 40000 (c) 400
  16. 16.Best estimate of 39 × 46? (a) 20000 (b) 200 (c) 2000
  17. 17.Best estimate of 42 × 40? (a) 160 (b) 16000 (c) 1600
  18. 18.Best estimate of 583 + 628? (a) 1400 (b) 1000 (c) 1200
  19. 19.Best estimate of 34 × 23? (a) 600 (b) 6000 (c) 60
  20. 20.Best estimate of 181 + 411? (a) 800 (b) 400 (c) 600
  21. 21.Best estimate of 66 × 21? (a) 14000 (b) 140 (c) 1400
  22. 22.Best estimate of 142 + 534? (a) 800 (b) 400 (c) 600
  23. 23.Best estimate of 449 + 356? (a) 600 (b) 800 (c) 1000
  24. 24.Best estimate of 39 × 36? (a) 1600 (b) 16000 (c) 160
  25. 25.Best estimate of 32 × 97? (a) 30000 (b) 300 (c) 3000
  26. 26.Best estimate of 704 + 601? (a) 1300 (b) 1500 (c) 1100
  27. 27.Best estimate of 541 + 862? (a) 1600 (b) 1400 (c) 1200
  28. 28.Best estimate of 221 + 689? (a) 1100 (b) 900 (c) 700
  29. 29.Best estimate of 197 + 382? (a) 800 (b) 600 (c) 400
  30. 30.Best estimate of 29 × 93? (a) 27000 (b) 2700 (c) 270
  31. 31.Best estimate of 16 × 89? (a) 1800 (b) 18000 (c) 180
  32. 32.Best estimate of 792 + 518? (a) 1500 (b) 1100 (c) 1300
  33. 33.Best estimate of 347 + 622? (a) 900 (b) 700 (c) 1100
  34. 34.Best estimate of 125 + 479? (a) 600 (b) 800 (c) 400
  35. 35.Best estimate of 89 × 49? (a) 450 (b) 4500 (c) 45000
  36. 36.Best estimate of 98 × 29? (a) 3000 (b) 30000 (c) 300
  37. 37.Best estimate of 653 + 410? (a) 1100 (b) 900 (c) 1300
  38. 38.Best estimate of 76 × 56? (a) 480 (b) 48000 (c) 4800
  39. 39.Best estimate of 12 × 24? (a) 20 (b) 200 (c) 2000
  40. 40.Best estimate of 581 + 684? (a) 1300 (b) 1500 (c) 1100

Answer key

  1. 1200
  2. 2400
  3. 1100
  4. 1400
  5. 1100
  6. 1200
  7. 1800
  8. 400
  9. 1400
  10. 2400
  11. 4500
  12. 2100
  13. 600
  14. 1600
  15. 4000
  16. 2000
  17. 1600
  18. 1200
  19. 600
  20. 600
  21. 1400
  22. 600
  23. 800
  24. 1600
  25. 3000
  26. 1300
  27. 1400
  28. 900
  29. 600
  30. 2700
  31. 1800
  32. 1300
  33. 900
  34. 600
  35. 4500
  36. 3000
  37. 1100
  38. 4800
  39. 200
  40. 1300

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