Mark against the correct answer
`6.3-2.8=?`

Options

A. 0.35
B. 3.5
C. 3.035
D. none of these

Answer

To solve the problem \( 6.3 - 2.8 \), we will follow these steps:

### Step 1: Align the numbers
Write the numbers one below the other, aligning the decimal points:
```
6.3
- 2.8
```

### Step 2: Subtract the numbers
Now, we will subtract starting from the rightmost digit (the tenths place):
- In the tenths place: \( 3 - 8 \) cannot be done directly, so we need to borrow 1 from the units place (6 becomes 5, and 3 becomes 13).
- Now, \( 13 - 8 = 5 \).

Next, move to the units place:
- After borrowing, we have \( 5 - 2 = 3 \).

### Step 3: Combine the results
Now, we combine the results from the subtraction:
- The result from the units place is 3 and from the tenths place is 5, giving us \( 3.5 \).

### Final Answer
Thus, \( 6.3 - 2.8 = 3.5 \).

### Conclusion
The correct answer is option B: \( 3.5 \).

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