What will come in the place of question mark (?) in following questions?
`2.1 xx 0.02 xx 6.3`= ?

Options

A. `0.2614`
B. `0.6642`
C. `0.2646`
D. `0.6214`

Answer

To solve the expression \( 2.1 \times 0.02 \times 6.3 \), we will follow these steps:

### Step 1: Multiply the first two numbers
First, we multiply \( 2.1 \) and \( 0.02 \).

\[ 2.1 \times 0.02 = 0.042 \]

### Step 2: Multiply the result with the third number
Next, we take the result from Step 1 and multiply it by \( 6.3 \).

\[ 0.042 \times 6.3 \]

To perform this multiplication, we can break it down:
- \( 0.042 \times 6.3 \) can be calculated as follows:

\[ 0.042 \times 6.3 = 0.2646 \]

### Step 3: Determine the position of the decimal point
Now, we need to determine the position of the decimal point in the final result.

- In \( 2.1 \), there is 1 digit after the decimal.
- In \( 0.02 \), there are 2 digits after the decimal.
- In \( 6.3 \), there is 1 digit after the decimal.

Adding these gives us a total of \( 1 + 2 + 1 = 4 \) digits after the decimal point in the final answer.

Thus, the final result is:

\[ 0.2646 \]

### Conclusion
The answer to the question \( 2.1 \times 0.02 \times 6.3 = ? \) is \( 0.2646 \).

### Options
Looking at the options provided:
1. 0.2614
2. 0.6642
3. 0.2646
4. 0.6214

The correct option is **3. 0.2646**.

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