Grade 6 Addition Worksheet 3: Solve the equation with 20 three-number addition problems.

I'll solve each addition problem step by step, carefully checking my calculations.

Let me work through all 20 problems:

Problem 1: 612 + 512 + 11
- 612 + 512 = 1124
- 1124 + 11 = 1135

Problem 2: 125 + 74 + 95
- 125 + 74 = 199
- 199 + 95 = 294

Problem 3: 916 + 51 + 437
- 916 + 51 = 967
- 967 + 437 = 1404

Problem 4: 189 + 191 + 96
- 189 + 191 = 380
- 380 + 96 = 476

Problem 5: 729 + 48 + 211
- 729 + 48 = 777
- 777 + 211 = 988

Problem 6: 139 + 92 + 164
- 139 + 92 = 231
- 231 + 164 = 395

Problem 7: 82 + 617 + 429
- 82 + 617 = 699
- 699 + 429 = 1128

Problem 8: 362 + 14 + 66
- 362 + 14 = 376
- 376 + 66 = 442

Problem 9: 825 + 131 + 77
- 825 + 131 = 956
- 956 + 77 = 1033

Problem 10: 72 + 436 + 85
- 72 + 436 = 508
- 508 + 85 = 593

Problem 11: 906 + 59 + 412
- 906 + 59 = 965
- 965 + 412 = 1377

Problem 12: 25 + 63 + 457
- 25 + 63 = 88
- 88 + 457 = 545

Problem 13: 638 + 802 + 55
- 638 + 802 = 1440
- 1440 + 55 = 1495

Problem 14: 217 + 306 + 74
- 217 + 306 = 523
- 523 + 74 = 597

Problem 15: 435 + 128 + 65
- 435 + 128 = 563
- 563 + 65 = 628

Problem 16: 568 + 219 + 18
- 568 + 219 = 787
- 787 + 18 = 805

Problem 17: 76 + 142 + 93
- 76 + 142 = 218
- 218 + 93 = 311

Problem 18: 928 + 52 + 41
- 928 + 52 = 980
- 980 + 41 = 1021

Problem 19: 687 + 36 + 47
- 687 + 36 = 723
- 723 + 47 = 770

Problem 20: 819 + 25 + 36
- 819 + 25 = 844
- 844 + 36 = 880

Final Answer:
1. 1135
2. 294
3. 1404
4. 476
5. 988
6. 395
7. 1128
8. 442
9. 1033
10. 593
11. 1377
12. 545
13. 1495
14. 597
15. 628
16. 805
17. 311
18. 1021
19. 770
20. 880