7.2, 72, 9, 54, 13.5, 28

Options

A. 72
B. 9
C. 28
D. 13.5

Explanation

To find the odd one out in the series: 7.2, 72, 9, 54, 13.5, 28, we will analyze the pattern of the series step by step.

### Step-by-Step Solution:

1. **Identify the Series**: The series given is 7.2, 72, 9, 54, 13.5, 28.

2. **Look for Patterns**:
- From 7.2 to 72:
- We can see that \( 7.2 \times 10 = 72 \).
- From 72 to 9:
- We can see that \( 72 \div 8 = 9 \).
- From 9 to 54:
- We can see that \( 9 \times 6 = 54 \).
- From 54 to 13.5:
- We can see that \( 54 \div 4 = 13.5 \).
- From 13.5 to 28:
- We can see that \( 13.5 \times 2 = 27 \) (but we have 28 in the series).

3. **Identify the Mistake**:
- The last operation should have resulted in 27, but instead, we have 28 in the series.
- This indicates that 28 does not follow the established pattern.

4. **Conclusion**:
- The odd one out in the series is 28. The correct number that should be in the series instead of 28 is 27.

### Final Answer:
The odd one out in the series is **28**.

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