Math worksheet for practicing subtraction with regrouping, focusing on problems involving zeros.

Problem: Subtracting 2-digit numbers with regrouping

The task involves solving subtraction problems and identifying the correct answer from the given options. Let's solve each problem step by step.

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#### 1. \( 800 - 515 \)

- Step 1: Subtract the ones place: \( 0 - 5 \). Since 0 is less than 5, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 5 = 5 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 1 = 8 \).

- Step 3: Subtract the hundreds place: \( 7 - 5 = 2 \).

- Final Answer: \( 800 - 515 = 285 \).

Correct Answer: \( 285 \)

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#### 2. \( 907 - 418 \)

- Step 1: Subtract the ones place: \( 7 - 8 \). Since 7 is less than 8, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 17 - 8 = 9 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 1 = 8 \).

- Step 3: Subtract the hundreds place: \( 8 - 4 = 4 \).

- Final Answer: \( 907 - 418 = 489 \).

Correct Answer: \( 489 \)

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#### 3. \( 600 - 231 \)

- Step 1: Subtract the ones place: \( 0 - 1 \). Since 0 is less than 1, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 1 = 9 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 3 = 6 \).

- Step 3: Subtract the hundreds place: \( 5 - 2 = 3 \).

- Final Answer: \( 600 - 231 = 369 \).

Correct Answer: \( 369 \)

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#### 4. \( 700 - 422 \)

- Step 1: Subtract the ones place: \( 0 - 2 \). Since 0 is less than 2, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 2 = 8 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 2 = 7 \).

- Step 3: Subtract the hundreds place: \( 6 - 4 = 2 \).

- Final Answer: \( 700 - 422 = 278 \).

Correct Answer: \( 278 \)

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#### 5. \( 203 - 129 \)

- Step 1: Subtract the ones place: \( 3 - 9 \). Since 3 is less than 9, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 13 - 9 = 4 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 2 = 7 \).

- Step 3: Subtract the hundreds place: \( 1 - 1 = 0 \).

- Final Answer: \( 203 - 129 = 74 \).

Correct Answer: \( 74 \)

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#### 6. \( 900 - 789 \)

- Step 1: Subtract the ones place: \( 0 - 9 \). Since 0 is less than 9, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 9 = 1 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 8 = 1 \).

- Step 3: Subtract the hundreds place: \( 8 - 7 = 1 \).

- Final Answer: \( 900 - 789 = 111 \).

Correct Answer: \( 111 \)

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#### 7. \( 800 - 458 \)

- Step 1: Subtract the ones place: \( 0 - 8 \). Since 0 is less than 8, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 8 = 2 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 5 = 4 \).

- Step 3: Subtract the hundreds place: \( 7 - 4 = 3 \).

- Final Answer: \( 800 - 458 = 342 \).

Correct Answer: \( 342 \)

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#### 8. \( 300 - 217 \)

- Step 1: Subtract the ones place: \( 0 - 7 \). Since 0 is less than 7, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 7 = 3 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 1 = 8 \).

- Step 3: Subtract the hundreds place: \( 2 - 2 = 0 \).

- Final Answer: \( 300 - 217 = 83 \).

Correct Answer: \( 83 \)

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#### 9. \( 200 - 156 \)

- Step 1: Subtract the ones place: \( 0 - 6 \). Since 0 is less than 6, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 6 = 4 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 5 = 4 \).

- Step 3: Subtract the hundreds place: \( 1 - 1 = 0 \).

- Final Answer: \( 200 - 156 = 44 \).

Correct Answer: \( 44 \)

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#### 10. \( 500 - 247 \)

- Step 1: Subtract the ones place: \( 0 - 7 \). Since 0 is less than 7, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 7 = 3 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 4 = 5 \).

- Step 3: Subtract the hundreds place: \( 4 - 2 = 2 \).

- Final Answer: \( 500 - 247 = 253 \).

Correct Answer: \( 253 \)

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#### 11. \( 400 - 275 \)

- Step 1: Subtract the ones place: \( 0 - 5 \). Since 0 is less than 5, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 10 - 5 = 5 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 7 = 2 \).

- Step 3: Subtract the hundreds place: \( 3 - 2 = 1 \).

- Final Answer: \( 400 - 275 = 125 \).

Correct Answer: \( 125 \)

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#### 12. \( 306 - 138 \)

- Step 1: Subtract the ones place: \( 6 - 8 \). Since 6 is less than 8, we need to borrow 1 from the tens place.
- After borrowing, the ones place becomes \( 16 - 8 = 8 \).
- The tens place becomes \( 9 \) (after borrowing).

- Step 2: Subtract the tens place: \( 9 - 3 = 6 \).

- Step 3: Subtract the hundreds place: \( 2 - 1 = 1 \).

- Final Answer: \( 306 - 138 = 168 \).

Correct Answer: \( 168 \)

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Final Answers:

\[
\boxed{285, 489, 369, 278, 74, 111, 342, 83, 44, 253, 125, 168}
\]