← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 128 · 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. 1.302 + 58 =
  2. 2.142 + 19 =
  3. 3.298 + 39 =
  4. 4.314 + 68 =
  5. 5.59 + 27 =
  6. 6.91 + 28 =
  7. 7.238 + 69 =
  8. 8.138 + 38 =
  9. 9.209 + 77 =
  10. 10.429 + 79 =
  11. 11.279 + 18 =
  12. 12.118 + 67 =
  13. 13.440 + 99 =
  14. 14.372 + 39 =
  15. 15.224 + 47 =
  16. 16.298 + 99 =
  17. 17.297 + 29 =
  18. 18.99 + 39 =
  19. 19.489 + 19 =
  20. 20.108 + 57 =
  21. 21.149 + 68 =
  22. 22.421 + 17 =
  23. 23.194 + 49 =
  24. 24.283 + 79 =
  25. 25.167 + 38 =
  26. 26.257 + 39 =
  27. 27.330 + 67 =
  28. 28.339 + 29 =
  29. 29.282 + 78 =
  30. 30.119 + 39 =
  31. 31.227 + 47 =
  32. 32.165 + 48 =
  33. 33.449 + 68 =
  34. 34.120 + 99 =
  35. 35.82 + 67 =
  36. 36.123 + 87 =
  37. 37.101 + 69 =
  38. 38.393 + 87 =
  39. 39.128 + 79 =
  40. 40.449 + 39 =

Answer key

  1. 360
  2. 161
  3. 337
  4. 382
  5. 86
  6. 119
  7. 307
  8. 176
  9. 286
  10. 508
  11. 297
  12. 185
  13. 539
  14. 411
  15. 271
  16. 397
  17. 326
  18. 138
  19. 508
  20. 165
  21. 217
  22. 438
  23. 243
  24. 362
  25. 205
  26. 296
  27. 397
  28. 368
  29. 360
  30. 158
  31. 274
  32. 213
  33. 517
  34. 219
  35. 149
  36. 210
  37. 170
  38. 480
  39. 207
  40. 488

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