← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 842 · 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. 1.438 + 57 =
  2. 2.491 + 18 =
  3. 3.194 + 28 =
  4. 4.417 + 57 =
  5. 5.353 + 39 =
  6. 6.356 + 38 =
  7. 7.97 + 98 =
  8. 8.93 + 99 =
  9. 9.54 + 18 =
  10. 10.337 + 67 =
  11. 11.50 + 68 =
  12. 12.446 + 47 =
  13. 13.35 + 78 =
  14. 14.334 + 39 =
  15. 15.212 + 28 =
  16. 16.492 + 89 =
  17. 17.482 + 69 =
  18. 18.238 + 79 =
  19. 19.202 + 77 =
  20. 20.64 + 78 =
  21. 21.354 + 18 =
  22. 22.164 + 58 =
  23. 23.100 + 49 =
  24. 24.348 + 89 =
  25. 25.82 + 79 =
  26. 26.157 + 37 =
  27. 27.26 + 39 =
  28. 28.325 + 17 =
  29. 29.369 + 97 =
  30. 30.406 + 28 =
  31. 31.233 + 68 =
  32. 32.293 + 77 =
  33. 33.272 + 47 =
  34. 34.75 + 48 =
  35. 35.47 + 18 =
  36. 36.47 + 58 =
  37. 37.40 + 28 =
  38. 38.222 + 28 =
  39. 39.76 + 29 =
  40. 40.115 + 18 =

Answer key

  1. 495
  2. 509
  3. 222
  4. 474
  5. 392
  6. 394
  7. 195
  8. 192
  9. 72
  10. 404
  11. 118
  12. 493
  13. 113
  14. 373
  15. 240
  16. 581
  17. 551
  18. 317
  19. 279
  20. 142
  21. 372
  22. 222
  23. 149
  24. 437
  25. 161
  26. 194
  27. 65
  28. 342
  29. 466
  30. 434
  31. 301
  32. 370
  33. 319
  34. 123
  35. 65
  36. 105
  37. 68
  38. 250
  39. 105
  40. 133

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