Addition practice worksheet with grid lines for solving three-digit addition problems.

Here is the solution to all 12 addition problems on the worksheet, with step-by-step explanations for each.

---

Problem 1: 996 + 978

```
996
+ 978
------
```

- Ones place: 6 + 8 = 14 → write down 4, carry 1
- Tens place: 9 + 7 + 1 (carry) = 17 → write down 7, carry 1
- Hundreds place: 9 + 9 + 1 (carry) = 19 → write down 9, carry 1
- Thousands place: carry 1 → write down 1

✔ Answer: 1974

---

Problem 2: 896 + 968

```
896
+ 968
------
```

- Ones: 6 + 8 = 14 → 4, carry 1
- Tens: 9 + 6 + 1 = 16 → 6, carry 1
- Hundreds: 8 + 9 + 1 = 18 → 8, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1864

---

Problem 3: 795 + 998

```
795
+ 998
------
```

- Ones: 5 + 8 = 13 → 3, carry 1
- Tens: 9 + 9 + 1 = 19 → 9, carry 1
- Hundreds: 7 + 9 + 1 = 17 → 7, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1793

---

Problem 4: 598 + 958

```
598
+ 958
------
```

- Ones: 8 + 8 = 16 → 6, carry 1
- Tens: 9 + 5 + 1 = 15 → 5, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1556

---

Problem 5: 597 + 938

```
597
+ 938
------
```

- Ones: 7 + 8 = 15 → 5, carry 1
- Tens: 9 + 3 + 1 = 13 → 3, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1535

---

Problem 6: 596 + 928

```
596
+ 928
------
```

- Ones: 6 + 8 = 14 → 4, carry 1
- Tens: 9 + 2 + 1 = 12 → 2, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1524

---

Problem 7: 595 + 968

```
595
+ 968
------
```

- Ones: 5 + 8 = 13 → 3, carry 1
- Tens: 9 + 6 + 1 = 16 → 6, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1563

---

Problem 8: 594 + 978

```
594
+ 978
------
```

- Ones: 4 + 8 = 12 → 2, carry 1
- Tens: 9 + 7 + 1 = 17 → 7, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1572

---

Problem 9: 593 + 998

```
593
+ 998
------
```

- Ones: 3 + 8 = 11 → 1, carry 1
- Tens: 9 + 9 + 1 = 19 → 9, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1591

---

Problem 10: 599 + 978

```
599
+ 978
------
```

- Ones: 9 + 8 = 17 → 7, carry 1
- Tens: 9 + 7 + 1 = 17 → 7, carry 1
- Hundreds: 5 + 9 + 1 = 15 → 5, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1577

---

Problem 11: 678 + 543

```
678
+ 543
------
```

- Ones: 8 + 3 = 11 → 1, carry 1
- Tens: 7 + 4 + 1 = 12 → 2, carry 1
- Hundreds: 6 + 5 + 1 = 12 → 2, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1221

---

Problem 12: 876 + 555

```
876
+ 555
------
```

- Ones: 6 + 5 = 11 → 1, carry 1
- Tens: 7 + 5 + 1 = 13 → 3, carry 1
- Hundreds: 8 + 5 + 1 = 14 → 4, carry 1
- Thousands: carry 1 → 1

✔ Answer: 1431

---

## ✔ Final Answers (in order):

1. 1974
2. 1864
3. 1793
4. 1556
5. 1535
6. 1524
7. 1563
8. 1572
9. 1591
10. 1577
11. 1221
12. 1431

You can fill these into the grid on your worksheet! Let me know if you’d like a printable version or step-by-step visuals.