← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 451 · 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. 1.221 + 97 =
  2. 2.170 + 59 =
  3. 3.269 + 98 =
  4. 4.136 + 28 =
  5. 5.149 + 17 =
  6. 6.249 + 48 =
  7. 7.355 + 29 =
  8. 8.83 + 87 =
  9. 9.305 + 37 =
  10. 10.327 + 17 =
  11. 11.81 + 57 =
  12. 12.284 + 17 =
  13. 13.255 + 19 =
  14. 14.199 + 29 =
  15. 15.43 + 38 =
  16. 16.192 + 89 =
  17. 17.72 + 58 =
  18. 18.40 + 39 =
  19. 19.32 + 59 =
  20. 20.56 + 27 =
  21. 21.345 + 68 =
  22. 22.68 + 88 =
  23. 23.167 + 28 =
  24. 24.262 + 28 =
  25. 25.273 + 79 =
  26. 26.315 + 67 =
  27. 27.428 + 87 =
  28. 28.451 + 28 =
  29. 29.118 + 27 =
  30. 30.158 + 38 =
  31. 31.183 + 68 =
  32. 32.307 + 27 =
  33. 33.346 + 47 =
  34. 34.290 + 58 =
  35. 35.147 + 77 =
  36. 36.286 + 67 =
  37. 37.437 + 68 =
  38. 38.107 + 27 =
  39. 39.184 + 47 =
  40. 40.92 + 78 =

Answer key

  1. 318
  2. 229
  3. 367
  4. 164
  5. 166
  6. 297
  7. 384
  8. 170
  9. 342
  10. 344
  11. 138
  12. 301
  13. 274
  14. 228
  15. 81
  16. 281
  17. 130
  18. 79
  19. 91
  20. 83
  21. 413
  22. 156
  23. 195
  24. 290
  25. 352
  26. 382
  27. 515
  28. 479
  29. 145
  30. 196
  31. 251
  32. 334
  33. 393
  34. 348
  35. 224
  36. 353
  37. 505
  38. 134
  39. 231
  40. 170

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