Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 193 · 40 questions

How to do it in your head (Round up, add back): Round the number you take away up to the next ten or hundred: 297 → 300 (3 too many). Take away the round number. Add back the extra, because you took away too much.

1. 1.719 − 599 =
2. 2.606 − 538 =
3. 3.985 − 587 =
4. 4.482 − 399 =
5. 5.973 − 199 =
6. 6.859 − 799 =
7. 7.852 − 198 =
8. 8.899 − 697 =
9. 9.925 − 697 =
10. 10.437 − 297 =
11. 11.663 − 287 =
12. 12.980 − 399 =
13. 13.380 − 268 =
14. 14.637 − 497 =
15. 15.797 − 698 =
16. 16.647 − 527 =
17. 17.838 − 699 =
18. 18.924 − 378 =
19. 19.559 − 168 =
20. 20.655 − 197 =
21. 21.894 − 437 =
22. 22.744 − 448 =
23. 23.747 − 698 =
24. 24.414 − 397 =
25. 25.695 − 297 =
26. 26.789 − 697 =
27. 27.862 − 499 =
28. 28.632 − 509 =
29. 29.818 − 367 =
30. 30.902 − 797 =
31. 31.700 − 197 =
32. 32.823 − 799 =
33. 33.917 − 258 =
34. 34.893 − 799 =
35. 35.465 − 397 =
36. 36.595 − 408 =
37. 37.692 − 638 =
38. 38.441 − 298 =
39. 39.972 − 668 =
40. 40.532 − 398 =

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