Subtraction by Rounding Worksheet

Mental maths lesson 21: Subtract by rounding up and adding back · Set 731 · 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. 1.526 − 298 =
2. 2.772 − 599 =
3. 3.631 − 498 =
4. 4.818 − 597 =
5. 5.404 − 297 =
6. 6.519 − 389 =
7. 7.454 − 397 =
8. 8.974 − 797 =
9. 9.366 − 299 =
10. 10.744 − 498 =
11. 11.668 − 599 =
12. 12.671 − 167 =
13. 13.884 − 497 =
14. 14.753 − 588 =
15. 15.479 − 337 =
16. 16.796 − 399 =
17. 17.581 − 197 =
18. 18.577 − 259 =
19. 19.597 − 497 =
20. 20.616 − 119 =
21. 21.439 − 148 =
22. 22.719 − 698 =
23. 23.881 − 398 =
24. 24.744 − 599 =
25. 25.571 − 398 =
26. 26.570 − 509 =
27. 27.609 − 457 =
28. 28.885 − 369 =
29. 29.937 − 699 =
30. 30.906 − 328 =
31. 31.744 − 697 =
32. 32.375 − 197 =
33. 33.797 − 698 =
34. 34.268 − 168 =
35. 35.947 − 299 =
36. 36.467 − 298 =
37. 37.969 − 207 =
38. 38.889 − 599 =
39. 39.877 − 798 =
40. 40.226 − 127 =

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