3-Digit Mental Addition and Subtraction Worksheet

Mental maths lesson 20: Add and subtract 3-digit numbers left to right · Set 327 · 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. 1.691 − 591 =
2. 2.284 + 489 =
3. 3.465 + 538 =
4. 4.433 − 235 =
5. 5.548 − 378 =
6. 6.777 + 221 =
7. 7.814 − 566 =
8. 8.678 − 256 =
9. 9.184 + 439 =
10. 10.606 − 473 =
11. 11.532 − 124 =
12. 12.515 − 196 =
13. 13.976 − 317 =
14. 14.473 − 291 =
15. 15.841 − 435 =
16. 16.704 − 461 =
17. 17.725 − 166 =
18. 18.514 + 253 =
19. 19.743 − 508 =
20. 20.501 − 134 =
21. 21.429 − 232 =
22. 22.646 + 233 =
23. 23.148 + 472 =
24. 24.275 + 123 =
25. 25.334 + 621 =
26. 26.606 + 454 =
27. 27.730 − 402 =
28. 28.924 − 283 =
29. 29.284 + 178 =
30. 30.471 + 409 =
31. 31.682 + 401 =
32. 32.877 − 442 =
33. 33.525 − 301 =
34. 34.191 + 448 =
35. 35.137 + 257 =
36. 36.980 − 719 =
37. 37.912 − 758 =
38. 38.703 − 134 =
39. 39.540 + 285 =
40. 40.335 + 555 =

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