3-Digit Mental Addition and Subtraction Worksheet

Mental maths lesson 20: Add and subtract 3-digit numbers left to right · Set 286 · 40 questions

How to do it in your head (Hundreds first): Keep the first number as it is and split the second into hundreds, tens and ones. Add (or take away) the hundreds first, then the tens. Finish with the ones — bridge through a ten if you need to.

1. 1.220 + 456 =
2. 2.647 − 482 =
3. 3.456 + 281 =
4. 4.716 + 336 =
5. 5.781 − 672 =
6. 6.763 − 479 =
7. 7.424 − 276 =
8. 8.535 − 233 =
9. 9.914 − 263 =
10. 10.291 + 662 =
11. 11.947 − 527 =
12. 12.730 − 188 =
13. 13.462 + 167 =
14. 14.453 + 329 =
15. 15.604 + 136 =
16. 16.594 + 384 =
17. 17.254 + 215 =
18. 18.795 − 445 =
19. 19.688 − 384 =
20. 20.433 − 141 =
21. 21.689 + 499 =
22. 22.506 − 283 =
23. 23.657 + 604 =
24. 24.480 − 325 =
25. 25.680 + 471 =
26. 26.641 + 188 =
27. 27.665 − 339 =
28. 28.508 + 471 =
29. 29.495 + 586 =
30. 30.780 − 533 =
31. 31.627 − 121 =
32. 32.404 + 499 =
33. 33.485 − 225 =
34. 34.562 − 432 =
35. 35.889 − 155 =
36. 36.934 − 794 =
37. 37.787 − 311 =
38. 38.764 + 671 =
39. 39.335 + 384 =
40. 40.704 − 409 =

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