Practice sheet for adding and subtracting 3-digit numbers.

The image you provided is a worksheet for practicing addition and subtraction of 3-digit numbers. Below, I will solve each problem step by step and explain the process.

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Worksheet: Adding/Subtracting 3-Digit Numbers (A)

#### Row 1
1. 501 + 803
- Add the numbers column by column:
- Ones place: \( 1 + 3 = 4 \)
- Tens place: \( 0 + 0 = 0 \)
- Hundreds place: \( 5 + 8 = 13 \)
- Result: \( 1304 \)

2. 538 - 523
- Subtract the numbers column by column:
- Ones place: \( 8 - 3 = 5 \)
- Tens place: \( 3 - 2 = 1 \)
- Hundreds place: \( 5 - 5 = 0 \)
- Result: \( 15 \)

3. 918 - 871
- Subtract the numbers column by column:
- Ones place: \( 8 - 1 = 7 \)
- Tens place: \( 1 - 7 \) (borrow 1 from hundreds place):
- Adjust: \( 11 - 7 = 4 \)
- Hundreds place: \( 8 - 8 = 0 \)
- Result: \( 47 \)

4. 163 + 514
- Add the numbers column by column:
- Ones place: \( 3 + 4 = 7 \)
- Tens place: \( 6 + 1 = 7 \)
- Hundreds place: \( 1 + 5 = 6 \)
- Result: \( 677 \)

5. 279 + 839
- Add the numbers column by column:
- Ones place: \( 9 + 9 = 18 \) (carry 1 to tens place)
- Tens place: \( 7 + 3 + 1 = 11 \) (carry 1 to hundreds place)
- Hundreds place: \( 2 + 8 + 1 = 11 \)
- Result: \( 1118 \)

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#### Row 2
1. 534 + 951
- Add the numbers column by column:
- Ones place: \( 4 + 1 = 5 \)
- Tens place: \( 3 + 5 = 8 \)
- Hundreds place: \( 5 + 9 = 14 \)
- Result: \( 1485 \)

2. 107 + 271
- Add the numbers column by column:
- Ones place: \( 7 + 1 = 8 \)
- Tens place: \( 0 + 7 = 7 \)
- Hundreds place: \( 1 + 2 = 3 \)
- Result: \( 378 \)

3. 691 + 832
- Add the numbers column by column:
- Ones place: \( 1 + 2 = 3 \)
- Tens place: \( 9 + 3 = 12 \) (carry 1 to hundreds place)
- Hundreds place: \( 6 + 8 + 1 = 15 \)
- Result: \( 1523 \)

4. 821 + 125
- Add the numbers column by column:
- Ones place: \( 1 + 5 = 6 \)
- Tens place: \( 2 + 2 = 4 \)
- Hundreds place: \( 8 + 1 = 9 \)
- Result: \( 946 \)

5. 520 - 355
- Subtract the numbers column by column:
- Ones place: \( 0 - 5 \) (borrow 1 from tens place):
- Adjust: \( 10 - 5 = 5 \)
- Tens place: \( 1 - 5 \) (borrow 1 from hundreds place):
- Adjust: \( 11 - 5 = 6 \)
- Hundreds place: \( 4 - 3 = 1 \)
- Result: \( 165 \)

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#### Row 3
1. 539 + 899
- Add the numbers column by column:
- Ones place: \( 9 + 9 = 18 \) (carry 1 to tens place)
- Tens place: \( 3 + 9 + 1 = 13 \) (carry 1 to hundreds place)
- Hundreds place: \( 5 + 8 + 1 = 14 \)
- Result: \( 1438 \)

2. 995 - 446
- Subtract the numbers column by column:
- Ones place: \( 5 - 6 \) (borrow 1 from tens place):
- Adjust: \( 15 - 6 = 9 \)
- Tens place: \( 8 - 4 = 4 \)
- Hundreds place: \( 9 - 4 = 5 \)
- Result: \( 549 \)

3. 820 + 178
- Add the numbers column by column:
- Ones place: \( 0 + 8 = 8 \)
- Tens place: \( 2 + 7 = 9 \)
- Hundreds place: \( 8 + 1 = 9 \)
- Result: \( 998 \)

4. 597 - 520
- Subtract the numbers column by column:
- Ones place: \( 7 - 0 = 7 \)
- Tens place: \( 9 - 2 = 7 \)
- Hundreds place: \( 5 - 5 = 0 \)
- Result: \( 77 \)

5. 804 - 744
- Subtract the numbers column by column:
- Ones place: \( 4 - 4 = 0 \)
- Tens place: \( 0 - 4 \) (borrow 1 from hundreds place):
- Adjust: \( 10 - 4 = 6 \)
- Hundreds place: \( 7 - 7 = 0 \)
- Result: \( 60 \)

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#### Row 4
1. 831 - 445
- Subtract the numbers column by column:
- Ones place: \( 1 - 5 \) (borrow 1 from tens place):
- Adjust: \( 11 - 5 = 6 \)
- Tens place: \( 2 - 4 \) (borrow 1 from hundreds place):
- Adjust: \( 12 - 4 = 8 \)
- Hundreds place: \( 7 - 4 = 3 \)
- Result: \( 386 \)

2. 929 - 629
- Subtract the numbers column by column:
- Ones place: \( 9 - 9 = 0 \)
- Tens place: \( 2 - 2 = 0 \)
- Hundreds place: \( 9 - 6 = 3 \)
- Result: \( 300 \)

3. 889 - 124
- Subtract the numbers column by column:
- Ones place: \( 9 - 4 = 5 \)
- Tens place: \( 8 - 2 = 6 \)
- Hundreds place: \( 8 - 1 = 7 \)
- Result: \( 765 \)

4. 662 + 847
- Add the numbers column by column:
- Ones place: \( 2 + 7 = 9 \)
- Tens place: \( 6 + 4 = 10 \) (carry 1 to hundreds place)
- Hundreds place: \( 6 + 8 + 1 = 15 \)
- Result: \( 1509 \)

5. 967 - 599
- Subtract the numbers column by column:
- Ones place: \( 7 - 9 \) (borrow 1 from tens place):
- Adjust: \( 17 - 9 = 8 \)
- Tens place: \( 5 - 9 \) (borrow 1 from hundreds place):
- Adjust: \( 15 - 9 = 6 \)
- Hundreds place: \( 8 - 5 = 3 \)
- Result: \( 368 \)

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#### Row 5
1. 985 + 606
- Add the numbers column by column:
- Ones place: \( 5 + 6 = 11 \) (carry 1 to tens place)
- Tens place: \( 8 + 0 + 1 = 9 \)
- Hundreds place: \( 9 + 6 = 15 \)
- Result: \( 1591 \)

2. 457 - 309
- Subtract the numbers column by column:
- Ones place: \( 7 - 9 \) (borrow 1 from tens place):
- Adjust: \( 17 - 9 = 8 \)
- Tens place: \( 4 - 0 \) (borrow 1 from hundreds place):
- Adjust: \( 14 - 0 = 4 \)
- Hundreds place: \( 3 - 3 = 0 \)
- Result: \( 148 \)

3. 595 + 215
- Add the numbers column by column:
- Ones place: \( 5 + 5 = 10 \) (carry 1 to tens place)
- Tens place: \( 9 + 1 + 1 = 11 \) (carry 1 to hundreds place)
- Hundreds place: \( 5 + 2 + 1 = 8 \)
- Result: \( 810 \)

4. 966 - 246
- Subtract the numbers column by column:
- Ones place: \( 6 - 6 = 0 \)
- Tens place: \( 6 - 4 = 2 \)
- Hundreds place: \( 9 - 2 = 7 \)
- Result: \( 720 \)

5. 348 - 199
- Subtract the numbers column by column:
- Ones place: \( 8 - 9 \) (borrow 1 from tens place):
- Adjust: \( 18 - 9 = 9 \)
- Tens place: \( 3 - 9 \) (borrow 1 from hundreds place):
- Adjust: \( 13 - 9 = 4 \)
- Hundreds place: \( 2 - 1 = 1 \)
- Result: \( 149 \)

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Final Answers

```
Row 1: 1304, 15, 47, 677, 1118
Row 2: 1485, 378, 1523, 946, 165
Row 3: 1438, 549, 998, 77, 60
Row 4: 386, 300, 765, 1509, 368
Row 5: 1591, 148, 810, 720, 149
```

Thus, the final boxed answer is:
\[
\boxed{1304, 15, 47, 677, 1118, 1485, 378, 1523, 946, 165, 1438, 549, 998, 77, 60, 386, 300, 765, 1509, 368, 1591, 148, 810, 720, 149}
\]