What will come in place of question mark (?) in the given question
11 5 4 4.5 ? 15

Options

A. 5
B. 7
C. 6
D. 8

Answer

To solve the problem step by step, we will analyze the given sequence: 11, 5, 4, 4.5, ?, 15.

### Step 1: Identify the relationship between the numbers
We need to find a pattern in the sequence. Let's look at how we can get from one number to the next.

### Step 2: Calculate the first transition (from 11 to 5)
To go from 11 to 5:
- Multiply 11 by 0.5:
\( 11 \times 0.5 = 5.5 \)
- Then subtract 0.5:
\( 5.5 - 0.5 = 5 \)

### Step 3: Calculate the second transition (from 5 to 4)
To go from 5 to 4:
- Multiply 5 by 1:
\( 5 \times 1 = 5 \)
- Then subtract 1:
\( 5 - 1 = 4 \)

### Step 4: Calculate the third transition (from 4 to 4.5)
To go from 4 to 4.5:
- Multiply 4 by 1.5:
\( 4 \times 1.5 = 6 \)
- Then subtract 1.5:
\( 6 - 1.5 = 4.5 \)

### Step 5: Calculate the fourth transition (from 4.5 to ?)
Now, we will apply the same pattern:
- Multiply 4.5 by 2:
\( 4.5 \times 2 = 9 \)
- Then subtract 2:
\( 9 - 2 = 7 \)

### Step 6: Calculate the fifth transition (from ? to 15)
To check if our answer is correct, we will calculate the next transition:
- Multiply 7 by 2.5:
\( 7 \times 2.5 = 17.5 \)
- Then subtract 2.5:
\( 17.5 - 2.5 = 15 \)

### Conclusion
The number that comes in place of the question mark (?) is **7**.