Addition & Subtraction Worksheet with 20 three-digit problems for practice.

Problem: Solve the Addition and Subtraction Problems

The worksheet contains 20 problems involving addition and subtraction of three-digit numbers. Below, I will solve each problem step by step.

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#### Problem 1:
$$
936 - 745
$$
- Subtract digit by digit from right to left:
- Units place: \(6 - 5 = 1\)
- Tens place: \(3 - 4\) (borrow 1 from hundreds place): \(13 - 4 = 9\)
- Hundreds place: \(8 - 7 = 1\) (after borrowing)
- Result: \(191\)

#### Problem 2:
$$
763 - 477
$$
- Subtract digit by digit from right to left:
- Units place: \(3 - 7\) (borrow 1 from tens place): \(13 - 7 = 6\)
- Tens place: \(5 - 7\) (borrow 1 from hundreds place): \(15 - 7 = 8\)
- Hundreds place: \(6 - 4 = 2\) (after borrowing)
- Result: \(286\)

#### Problem 3:
$$
975 - 418
$$
- Subtract digit by digit from right to left:
- Units place: \(5 - 8\) (borrow 1 from tens place): \(15 - 8 = 7\)
- Tens place: \(6 - 1 = 5\) (after borrowing)
- Hundreds place: \(9 - 4 = 5\)
- Result: \(557\)

#### Problem 4:
$$
261 + 578
$$
- Add digit by digit from right to left:
- Units place: \(1 + 8 = 9\)
- Tens place: \(6 + 7 = 13\) (carry 1 to hundreds place)
- Hundreds place: \(2 + 5 + 1 = 8\) (after carrying)
- Result: \(839\)

#### Problem 5:
$$
625 - 495
$$
- Subtract digit by digit from right to left:
- Units place: \(5 - 5 = 0\)
- Tens place: \(2 - 9\) (borrow 1 from hundreds place): \(12 - 9 = 3\)
- Hundreds place: \(5 - 4 = 1\) (after borrowing)
- Result: \(130\)

#### Problem 6:
$$
709 - 439
$$
- Subtract digit by digit from right to left:
- Units place: \(9 - 9 = 0\)
- Tens place: \(0 - 3\) (borrow 1 from hundreds place): \(10 - 3 = 7\)
- Hundreds place: \(6 - 4 = 2\) (after borrowing)
- Result: \(270\)

#### Problem 7:
$$
654 - 543
$$
- Subtract digit by digit from right to left:
- Units place: \(4 - 3 = 1\)
- Tens place: \(5 - 4 = 1\)
- Hundreds place: \(6 - 5 = 1\)
- Result: \(111\)

#### Problem 8:
$$
273 + 528
$$
- Add digit by digit from right to left:
- Units place: \(3 + 8 = 11\) (carry 1 to tens place)
- Tens place: \(7 + 2 + 1 = 10\) (carry 1 to hundreds place)
- Hundreds place: \(2 + 5 + 1 = 8\) (after carrying)
- Result: \(801\)

#### Problem 9:
$$
274 + 528
$$
- Add digit by digit from right to left:
- Units place: \(4 + 8 = 12\) (carry 1 to tens place)
- Tens place: \(7 + 2 + 1 = 10\) (carry 1 to hundreds place)
- Hundreds place: \(2 + 5 + 1 = 8\) (after carrying)
- Result: \(802\)

#### Problem 10:
$$
347 - 289
$$
- Subtract digit by digit from right to left:
- Units place: \(7 - 9\) (borrow 1 from tens place): \(17 - 9 = 8\)
- Tens place: \(3 - 8\) (borrow 1 from hundreds place): \(13 - 8 = 5\)
- Hundreds place: \(2 - 2 = 0\) (after borrowing)
- Result: \(058\) or simply \(58\)

#### Problem 11:
$$
999 + 339
$$
- Add digit by digit from right to left:
- Units place: \(9 + 9 = 18\) (carry 1 to tens place)
- Tens place: \(9 + 3 + 1 = 13\) (carry 1 to hundreds place)
- Hundreds place: \(9 + 3 + 1 = 13\) (carry 1 to thousands place)
- Result: \(1338\)

#### Problem 12:
$$
639 - 165
$$
- Subtract digit by digit from right to left:
- Units place: \(9 - 5 = 4\)
- Tens place: \(3 - 6\) (borrow 1 from hundreds place): \(13 - 6 = 7\)
- Hundreds place: \(5 - 1 = 4\) (after borrowing)
- Result: \(474\)

#### Problem 13:
$$
352 - 109
$$
- Subtract digit by digit from right to left:
- Units place: \(2 - 9\) (borrow 1 from tens place): \(12 - 9 = 3\)
- Tens place: \(4 - 0 = 4\) (after borrowing)
- Hundreds place: \(3 - 1 = 2\)
- Result: \(243\)

#### Problem 14:
$$
356 + 749
$$
- Add digit by digit from right to left:
- Units place: \(6 + 9 = 15\) (carry 1 to tens place)
- Tens place: \(5 + 4 + 1 = 10\) (carry 1 to hundreds place)
- Hundreds place: \(3 + 7 + 1 = 11\) (carry 1 to thousands place)
- Result: \(1105\)

#### Problem 15:
$$
238 + 597
$$
- Add digit by digit from right to left:
- Units place: \(8 + 7 = 15\) (carry 1 to tens place)
- Tens place: \(3 + 9 + 1 = 13\) (carry 1 to hundreds place)
- Hundreds place: \(2 + 5 + 1 = 8\) (after carrying)
- Result: \(835\)

#### Problem 16:
$$
359 - 150
$$
- Subtract digit by digit from right to left:
- Units place: \(9 - 0 = 9\)
- Tens place: \(5 - 5 = 0\)
- Hundreds place: \(3 - 1 = 2\)
- Result: \(209\)

#### Problem 17:
$$
677 + 970
$$
- Add digit by digit from right to left:
- Units place: \(7 + 0 = 7\)
- Tens place: \(7 + 7 = 14\) (carry 1 to hundreds place)
- Hundreds place: \(6 + 9 + 1 = 16\) (carry 1 to thousands place)
- Result: \(1647\)

#### Problem 18:
$$
109 + 889
$$
- Add digit by digit from right to left:
- Units place: \(9 + 9 = 18\) (carry 1 to tens place)
- Tens place: \(0 + 8 + 1 = 9\)
- Hundreds place: \(1 + 8 = 9\)
- Result: \(998\)

#### Problem 19:
$$
374 + 465
$$
- Add digit by digit from right to left:
- Units place: \(4 + 5 = 9\)
- Tens place: \(7 + 6 = 13\) (carry 1 to hundreds place)
- Hundreds place: \(3 + 4 + 1 = 8\) (after carrying)
- Result: \(839\)

#### Problem 20:
$$
749 - 664
$$
- Subtract digit by digit from right to left:
- Units place: \(9 - 4 = 5\)
- Tens place: \(4 - 6\) (borrow 1 from hundreds place): \(14 - 6 = 8\)
- Hundreds place: \(6 - 6 = 0\) (after borrowing)
- Result: \(085\) or simply \(85\)

---

Final Answers:

$$
\boxed{
\begin{array}{ll}
1. & 191 \\
2. & 286 \\
3. & 557 \\
4. & 839 \\
5. & 130 \\
6. & 270 \\
7. & 111 \\
8. & 801 \\
9. & 802 \\
10. & 58 \\
11. & 1338 \\
12. & 474 \\
13. & 243 \\
14. & 1105 \\
15. & 835 \\
16. & 209 \\
17. & 1647 \\
18. & 998 \\
19. & 839 \\
20. & 85 \\
\end{array}
}
$$