← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 498 · 40 questions
TalentJR

The fast method (Round up, then fix): Round the number ending in 7, 8 or 9 up to the next ten: 39 → 40. Add the round number. Take away the extra you added (here 1).

NameDateTime takenScore ___ / 40
  1. 1.479 + 27 =
  2. 2.284 + 39 =
  3. 3.135 + 47 =
  4. 4.73 + 67 =
  5. 5.225 + 38 =
  6. 6.81 + 27 =
  7. 7.252 + 29 =
  8. 8.453 + 19 =
  9. 9.156 + 19 =
  10. 10.323 + 17 =
  11. 11.432 + 77 =
  12. 12.36 + 87 =
  13. 13.49 + 58 =
  14. 14.95 + 99 =
  15. 15.316 + 78 =
  16. 16.105 + 97 =
  17. 17.440 + 37 =
  18. 18.232 + 89 =
  19. 19.265 + 47 =
  20. 20.62 + 17 =
  21. 21.418 + 28 =
  22. 22.139 + 18 =
  23. 23.212 + 97 =
  24. 24.243 + 27 =
  25. 25.480 + 18 =
  26. 26.195 + 68 =
  27. 27.479 + 27 =
  28. 28.147 + 29 =
  29. 29.170 + 49 =
  30. 30.116 + 69 =
  31. 31.84 + 48 =
  32. 32.496 + 37 =
  33. 33.135 + 39 =
  34. 34.76 + 49 =
  35. 35.495 + 58 =
  36. 36.120 + 29 =
  37. 37.387 + 49 =
  38. 38.250 + 28 =
  39. 39.99 + 17 =
  40. 40.45 + 79 =

Answer key

  1. 506
  2. 323
  3. 182
  4. 140
  5. 263
  6. 108
  7. 281
  8. 472
  9. 175
  10. 340
  11. 509
  12. 123
  13. 107
  14. 194
  15. 394
  16. 202
  17. 477
  18. 321
  19. 312
  20. 79
  21. 446
  22. 157
  23. 309
  24. 270
  25. 498
  26. 263
  27. 506
  28. 176
  29. 219
  30. 185
  31. 132
  32. 533
  33. 174
  34. 125
  35. 553
  36. 149
  37. 436
  38. 278
  39. 116
  40. 124

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