What will come in place of the question mark (?) in thee following number series?
48 23 ? 4.25 1.125

Options

A. 10.5
B. 10
C. 2.5
D. 11

Answer

To find the missing number in the series: 48, 23, ?, 4.25, 1.125, we can analyze the pattern in the series.

### Step-by-Step Solution:

1. **Identify the relationship between the numbers:**
- The first number is 48 and the second number is 23.
- To find a relationship, we can see if there is a multiplication or division pattern.

2. **Calculate the relationship between 48 and 23:**
- If we take 23 and perform some operations to get 48, we can multiply 23 by 2 and then add 2:
\[ 23 \times 2 + 2 = 46 + 2 = 48 \]

3. **Now, let's look at the next number in the series, which is 4.25:**
- We can check if there is a similar operation that can be applied here. Let's take the next number, 1.125, and see if we can find a relationship:
\[ 1.125 \times 2 = 2.25 \]
- Now, if we add 2 to this result:
\[ 2.25 + 2 = 4.25 \]

4. **Using the same pattern to find the missing number:**
- We have established that the pattern is to take a number, multiply it by 2, and then add 2.
- We need to find the missing number (let's call it x) such that:
\[ x \times 2 + 2 = 23 \]

5. **Solving for x:**
- Rearranging the equation:
\[ x \times 2 = 23 - 2 \]
\[ x \times 2 = 21 \]
\[ x = \frac{21}{2} = 10.5 \]

6. **Conclusion:**
- The missing number in the series is 10.5.

### Final Answer:
The value that comes in place of the question mark (?) is **10.5**.