832.58-242.31=779.84-?

Options

A. 189.57
B. 199.57
C. 295.05
D. 170.57

Answer

To solve the equation \( 832.58 - 242.31 = 779.84 - ? \), we will follow these steps:

### Step 1: Calculate the left side of the equation
We first need to perform the subtraction on the left side:

\[ 832.58 - 242.31 \]

### Step 2: Perform the subtraction
Align the numbers by their decimal points and subtract:

```
832.58
- 242.31
_________
```

Starting from the rightmost digit:
- In the hundredths place: \( 8 - 1 = 7 \)
- In the tenths place: \( 5 - 3 = 2 \)
- In the units place: \( 2 - 2 = 0 \)
- In the tens place: \( 3 - 4 \) requires borrowing, so we take 1 from the 8 (making it 7), and we have \( 13 - 4 = 9 \)
- In the hundreds place: \( 7 - 2 = 5 \)

Putting it all together, we get:

\[ 832.58 - 242.31 = 590.27 \]

### Step 3: Set up the equation
Now we can set up the equation based on our calculation:

\[ 590.27 = 779.84 - ? \]

### Step 4: Rearrange to find the question mark
To find the question mark, we rearrange the equation:

\[ ? = 779.84 - 590.27 \]

### Step 5: Perform the subtraction
Now we will perform the subtraction on the right side:

```
779.84
- 590.27
_________
```

Starting from the rightmost digit:
- In the hundredths place: \( 4 - 7 \) requires borrowing, so we take 1 from the 8 (making it 7), and we have \( 14 - 7 = 7 \)
- In the tenths place: \( 7 - 2 = 5 \)
- In the units place: \( 9 - 0 = 9 \)
- In the tens place: \( 7 - 9 \) requires borrowing, so we take 1 from the 7 (making it 6), and we have \( 17 - 9 = 8 \)
- In the hundreds place: \( 6 - 5 = 1 \)

Putting it all together, we get:

\[ 779.84 - 590.27 = 189.57 \]

### Final Answer
Thus, the value of the question mark is:

\[ ? = 189.57 \]