← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 313 · 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. 1.391 + 89 =
  2. 2.472 + 48 =
  3. 3.400 + 59 =
  4. 4.345 + 17 =
  5. 5.100 + 89 =
  6. 6.294 + 98 =
  7. 7.336 + 68 =
  8. 8.77 + 57 =
  9. 9.165 + 99 =
  10. 10.53 + 89 =
  11. 11.282 + 28 =
  12. 12.207 + 77 =
  13. 13.41 + 89 =
  14. 14.334 + 77 =
  15. 15.178 + 37 =
  16. 16.399 + 37 =
  17. 17.135 + 38 =
  18. 18.137 + 67 =
  19. 19.103 + 38 =
  20. 20.483 + 29 =
  21. 21.250 + 29 =
  22. 22.433 + 78 =
  23. 23.299 + 67 =
  24. 24.394 + 59 =
  25. 25.400 + 99 =
  26. 26.71 + 69 =
  27. 27.356 + 58 =
  28. 28.475 + 88 =
  29. 29.324 + 49 =
  30. 30.97 + 37 =
  31. 31.328 + 17 =
  32. 32.383 + 58 =
  33. 33.412 + 39 =
  34. 34.357 + 87 =
  35. 35.146 + 39 =
  36. 36.63 + 37 =
  37. 37.334 + 28 =
  38. 38.40 + 37 =
  39. 39.137 + 17 =
  40. 40.260 + 49 =

Answer key

  1. 480
  2. 520
  3. 459
  4. 362
  5. 189
  6. 392
  7. 404
  8. 134
  9. 264
  10. 142
  11. 310
  12. 284
  13. 130
  14. 411
  15. 215
  16. 436
  17. 173
  18. 204
  19. 141
  20. 512
  21. 279
  22. 511
  23. 366
  24. 453
  25. 499
  26. 140
  27. 414
  28. 563
  29. 373
  30. 134
  31. 345
  32. 441
  33. 451
  34. 444
  35. 185
  36. 100
  37. 362
  38. 77
  39. 154
  40. 309

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