Find the wrong number in the following number series.
2,3,6,15,45,156.5,630

Options

A. A)2
B. B)15
C. C)3
D. D)156.5

Answer

To find the wrong number in the given series: 2, 3, 6, 15, 45, 156.5, 630, we will analyze the pattern of the series step by step.

### Step 1: Identify the pattern
Let's examine the relationship between consecutive terms in the series.

1. **First term (2)**:
- Multiply by 1.5 to get the second term.
- \( 2 \times 1.5 = 3 \)

2. **Second term (3)**:
- Multiply by 2 to get the third term.
- \( 3 \times 2 = 6 \)

3. **Third term (6)**:
- Multiply by 2.5 to get the fourth term.
- \( 6 \times 2.5 = 15 \)

4. **Fourth term (15)**:
- Multiply by 3 to get the fifth term.
- \( 15 \times 3 = 45 \)

5. **Fifth term (45)**:
- Multiply by 3.5 to get the sixth term.
- \( 45 \times 3.5 = 157.5 \)

6. **Sixth term (157.5)**:
- Multiply by 4 to get the seventh term.
- \( 157.5 \times 4 = 630 \)

### Step 2: Compare with the given series
Now, let's compare the calculated sixth term (157.5) with the given sixth term in the series (156.5).

- The calculated sixth term is **157.5**, but the series has **156.5**.

### Conclusion
Since the sixth term in the series should be **157.5** but is incorrectly listed as **156.5**, we conclude that the wrong number in the series is:

**Wrong number: 156.5**