Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 565 · 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. 1.776 − 698 =
2. 2.895 − 598 =
3. 3.451 − 399 =
4. 4.521 − 318 =
5. 5.765 − 498 =
6. 6.974 − 799 =
7. 7.651 − 437 =
8. 8.718 − 228 =
9. 9.632 − 197 =
10. 10.512 − 438 =
11. 11.874 − 687 =
12. 12.787 − 388 =
13. 13.878 − 799 =
14. 14.908 − 298 =
15. 15.628 − 467 =
16. 16.849 − 209 =
17. 17.543 − 398 =
18. 18.346 − 297 =
19. 19.925 − 679 =
20. 20.795 − 399 =
21. 21.979 − 297 =
22. 22.179 − 129 =
23. 23.730 − 558 =
24. 24.939 − 517 =
25. 25.763 − 568 =
26. 26.613 − 489 =
27. 27.821 − 398 =
28. 28.684 − 599 =
29. 29.991 − 208 =
30. 30.984 − 188 =
31. 31.351 − 297 =
32. 32.413 − 268 =
33. 33.903 − 798 =
34. 34.456 − 398 =
35. 35.528 − 119 =
36. 36.366 − 199 =
37. 37.561 − 339 =
38. 38.904 − 197 =
39. 39.925 − 377 =
40. 40.666 − 597 =

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