Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 527 · 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. 1.768 − 697 =
2. 2.872 − 647 =
3. 3.679 − 608 =
4. 4.868 − 799 =
5. 5.701 − 198 =
6. 6.721 − 319 =
7. 7.327 − 259 =
8. 8.755 − 599 =
9. 9.691 − 499 =
10. 10.674 − 598 =
11. 11.776 − 598 =
12. 12.323 − 227 =
13. 13.433 − 297 =
14. 14.364 − 228 =
15. 15.975 − 599 =
16. 16.638 − 498 =
17. 17.456 − 258 =
18. 18.648 − 327 =
19. 19.652 − 128 =
20. 20.835 − 367 =
21. 21.661 − 197 =
22. 22.427 − 197 =
23. 23.919 − 468 =
24. 24.859 − 598 =
25. 25.922 − 698 =
26. 26.813 − 799 =
27. 27.709 − 299 =
28. 28.723 − 358 =
29. 29.928 − 797 =
30. 30.304 − 198 =
31. 31.427 − 257 =
32. 32.820 − 597 =
33. 33.830 − 799 =
34. 34.906 − 799 =
35. 35.912 − 619 =
36. 36.436 − 397 =
37. 37.888 − 797 =
38. 38.959 − 797 =
39. 39.829 − 378 =
40. 40.561 − 397 =

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