Question

Solve multi-digit subtraction problems
Estimate differences
Use various subtraction ?
Solve real world problems

Answer 1

Sure! Let's go through some multi-digit subtraction problems, estimates, and real-world application problems.

### Multi-Digit Subtraction Problems

1. **Problem**: \( 582 - 247 \)

**Solution**:
```
582
- 247
------
335
```
So, \( 582 - 247 = 335 \).

2. **Problem**: \( 9453 - 6789 \)

**Solution**:
```
9453
- 6789
------
2664
```
Thus, \( 9453 - 6789 = 2664 \).

### Estimating Differences

To estimate a subtraction, we round the numbers to the nearest ten or hundred.

1. **Problem**: Estimate \( 572 - 289 \)

**Estimation**: \( 570 - 290 = 280 \) (rounded to nearest tens)

2. **Problem**: Estimate \( 4632 - 2789 \)

**Estimation**: \( 4600 - 2800 = 1800 \) (rounded to nearest hundreds)

### Various Subtraction Strategies

1. **Standard Algorithm**: This is what we used above for multi-digit subtraction.
2. **Counting Up**: Instead of subtracting, count how many you need to add to get from the smaller number to the larger one.
3. **Breaking Numbers Apart**: Break the numbers down into smaller, manageable parts.

**Example**: \( 839 - 274 \)
- Break it down:
- \( 839 - 200 = 639\)
- \( 639 - 70 = 569\)
- \( 569 - 4 = 565\)

Thus, \( 839 - 274 = 565 \).

### Solving Real-World Problems

1. **Problem**: A bookstore had 1,200 books. After a sale, 458 books were sold. How many books are left?

**Solution**:
- \( 1200 - 458 = 742 \)
- Therefore, there are 742 books left.

2. **Problem**: A car traveled 375 miles in the first part of the journey and then traveled 189 miles in the second part. How many miles did the car travel in total?

**Note**: This is an addition problem, but we can think about it in terms of subtraction from a certain total. If the total distance it could travel is 700 miles, we could look at how much is left after both legs.
- Total: \( 700 - (375 + 189) = 700 - 564 = 136 \)
- The car can still travel 136 miles.

3. **Problem**: Maria has $500 in her bank account. She spends $189 on groceries and $275 on bills. How much money does she have left?

**Solution**:
- First, find the total amount spent:
\[
189 + 275 = 464
\]
- Then subtract from the total money:
\[
500 - 464 = 36
\]
- Thus, Maria has $36 left.

Feel free to ask for any specific problems or areas you'd like to explore further!