← Add by rounding lesson New set →

Add by Rounding Worksheet

Speed calculation lesson 2: Add by rounding · Set 646 · 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. 1.93 + 37 =
  2. 2.345 + 79 =
  3. 3.318 + 27 =
  4. 4.182 + 19 =
  5. 5.107 + 68 =
  6. 6.189 + 97 =
  7. 7.239 + 58 =
  8. 8.345 + 39 =
  9. 9.309 + 58 =
  10. 10.103 + 48 =
  11. 11.385 + 37 =
  12. 12.467 + 49 =
  13. 13.82 + 98 =
  14. 14.25 + 77 =
  15. 15.445 + 88 =
  16. 16.107 + 48 =
  17. 17.222 + 19 =
  18. 18.389 + 79 =
  19. 19.403 + 29 =
  20. 20.342 + 28 =
  21. 21.44 + 49 =
  22. 22.391 + 97 =
  23. 23.129 + 18 =
  24. 24.133 + 89 =
  25. 25.201 + 47 =
  26. 26.132 + 28 =
  27. 27.194 + 87 =
  28. 28.351 + 48 =
  29. 29.160 + 68 =
  30. 30.356 + 68 =
  31. 31.53 + 17 =
  32. 32.350 + 18 =
  33. 33.205 + 37 =
  34. 34.58 + 58 =
  35. 35.490 + 57 =
  36. 36.230 + 47 =
  37. 37.498 + 78 =
  38. 38.497 + 69 =
  39. 39.340 + 28 =
  40. 40.86 + 98 =

Answer key

  1. 130
  2. 424
  3. 345
  4. 201
  5. 175
  6. 286
  7. 297
  8. 384
  9. 367
  10. 151
  11. 422
  12. 516
  13. 180
  14. 102
  15. 533
  16. 155
  17. 241
  18. 468
  19. 432
  20. 370
  21. 93
  22. 488
  23. 147
  24. 222
  25. 248
  26. 160
  27. 281
  28. 399
  29. 228
  30. 424
  31. 70
  32. 368
  33. 242
  34. 116
  35. 547
  36. 277
  37. 576
  38. 566
  39. 368
  40. 184

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