3 Digit Addition Worksheets with Answer Key - Free Printable

Let's solve each of the three-digit addition problems step by step. We'll add the numbers column by column, starting from the right (ones place), and carry over when necessary.

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1. 729 + 892

```
729
+ 892
-----
```

- Ones: 9 + 2 = 11 → write down 1, carry over 1
- Tens: 2 + 9 = 11, plus carry 1 = 12 → write down 2, carry over 1
- Hundreds: 7 + 8 = 15, plus carry 1 = 16

✔ Answer: 1621

---

2. 201 + 814

```
201
+ 814
-----
```

- Ones: 1 + 4 = 5
- Tens: 0 + 1 = 1
- Hundreds: 2 + 8 = 10

✔ Answer: 1015

---

3. 196 + 236

```
196
+ 236
-----
```

- Ones: 6 + 6 = 12 → write 2, carry 1
- Tens: 9 + 3 = 12, plus carry 1 = 13 → write 3, carry 1
- Hundreds: 1 + 2 = 3, plus carry 1 = 4

✔ Answer: 432

---

4. 664 + 232

```
664
+ 232
-----
```

- Ones: 4 + 2 = 6
- Tens: 6 + 3 = 9
- Hundreds: 6 + 2 = 8

✔ Answer: 896

---

5. 495 + 178

```
495
+ 178
-----
```

- Ones: 5 + 8 = 13 → write 3, carry 1
- Tens: 9 + 7 = 16, plus carry 1 = 17 → write 7, carry 1
- Hundreds: 4 + 1 = 5, plus carry 1 = 6

✔ Answer: 673

---

6. 835 + 707

```
835
+ 707
-----
```

- Ones: 5 + 7 = 12 → write 2, carry 1
- Tens: 3 + 0 = 3, plus carry 1 = 4
- Hundreds: 8 + 7 = 15

✔ Answer: 1542

---

7. 498 + 553

```
498
+ 553
-----
```

- Ones: 8 + 3 = 11 → write 1, carry 1
- Tens: 9 + 5 = 14, plus carry 1 = 15 → write 5, carry 1
- Hundreds: 4 + 5 = 9, plus carry 1 = 10

✔ Answer: 1051

---

8. 972 + 153

```
972
+ 153
-----
```

- Ones: 2 + 3 = 5
- Tens: 7 + 5 = 12 → write 2, carry 1
- Hundreds: 9 + 1 = 10, plus carry 1 = 11

✔ Answer: 1125

---

9. 792 + 135

```
792
+ 135
-----
```

- Ones: 2 + 5 = 7
- Tens: 9 + 3 = 12 → write 2, carry 1
- Hundreds: 7 + 1 = 8, plus carry 1 = 9

✔ Answer: 927

---

10. 888 + 249

```
888
+ 249
-----
```

- Ones: 8 + 9 = 17 → write 7, carry 1
- Tens: 8 + 4 = 12, plus carry 1 = 13 → write 3, carry 1
- Hundreds: 8 + 2 = 10, plus carry 1 = 11

✔ Answer: 1137

---

11. 189 + 918

```
189
+ 918
-----
```

- Ones: 9 + 8 = 17 → write 7, carry 1
- Tens: 8 + 1 = 9, plus carry 1 = 10 → write 0, carry 1
- Hundreds: 1 + 9 = 10, plus carry 1 = 11

✔ Answer: 1107

---

12. 649 + 232

```
649
+ 232
-----
```

- Ones: 9 + 2 = 11 → write 1, carry 1
- Tens: 4 + 3 = 7, plus carry 1 = 8
- Hundreds: 6 + 2 = 8

✔ Answer: 881

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✔ Final Answers:

| Problem | Answer |
|--------|--------|
| 729 + 892 | 1621 |
| 201 + 814 | 1015 |
| 196 + 236 | 432 |
| 664 + 232 | 896 |
| 495 + 178 | 673 |
| 835 + 707 | 1542 |
| 498 + 553 | 1051 |
| 972 + 153 | 1125 |
| 792 + 135 | 927 |
| 888 + 249 | 1137 |
| 189 + 918 | 1107 |
| 649 + 232 | 881 |

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Let me know if you'd like this formatted as a printable answer sheet!