← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 227 · 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. 1.431 + 39 =
  2. 2.444 + 58 =
  3. 3.218 + 69 =
  4. 4.354 + 87 =
  5. 5.402 + 79 =
  6. 6.494 + 19 =
  7. 7.453 + 59 =
  8. 8.435 + 88 =
  9. 9.482 + 18 =
  10. 10.97 + 68 =
  11. 11.159 + 18 =
  12. 12.424 + 67 =
  13. 13.384 + 77 =
  14. 14.172 + 68 =
  15. 15.405 + 39 =
  16. 16.311 + 97 =
  17. 17.293 + 78 =
  18. 18.450 + 57 =
  19. 19.328 + 48 =
  20. 20.226 + 39 =
  21. 21.136 + 38 =
  22. 22.56 + 58 =
  23. 23.142 + 18 =
  24. 24.87 + 97 =
  25. 25.321 + 89 =
  26. 26.346 + 88 =
  27. 27.438 + 79 =
  28. 28.494 + 29 =
  29. 29.133 + 98 =
  30. 30.375 + 98 =
  31. 31.339 + 18 =
  32. 32.181 + 37 =
  33. 33.117 + 68 =
  34. 34.416 + 69 =
  35. 35.178 + 39 =
  36. 36.441 + 67 =
  37. 37.295 + 37 =
  38. 38.424 + 47 =
  39. 39.274 + 48 =
  40. 40.491 + 37 =

Answer key

  1. 470
  2. 502
  3. 287
  4. 441
  5. 481
  6. 513
  7. 512
  8. 523
  9. 500
  10. 165
  11. 177
  12. 491
  13. 461
  14. 240
  15. 444
  16. 408
  17. 371
  18. 507
  19. 376
  20. 265
  21. 174
  22. 114
  23. 160
  24. 184
  25. 410
  26. 434
  27. 517
  28. 523
  29. 231
  30. 473
  31. 357
  32. 218
  33. 185
  34. 485
  35. 217
  36. 508
  37. 332
  38. 471
  39. 322
  40. 528

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