IN the following questions a number series is given in which one number is wrong. Find out the wrong number. Do not consider alternate series?
7 92 173 250 323 394 457

Options

A. 323
B. 92
C. 394
D. 250

Answer

To find the wrong number in the series: 7, 92, 173, 250, 323, 394, 457, we will analyze the differences between consecutive numbers and identify any inconsistencies.

### Step-by-Step Solution:

1. **Identify the Differences:**
- Calculate the differences between consecutive numbers:
- 92 - 7 = 85
- 173 - 92 = 81
- 250 - 173 = 77
- 323 - 250 = 73
- 394 - 323 = 71
- 457 - 394 = 63

So, the differences are: 85, 81, 77, 73, 71, 63.

2. **Look for a Pattern in Differences:**
- The differences seem to decrease by 4 initially:
- 85 to 81 (decrease by 4)
- 81 to 77 (decrease by 4)
- 77 to 73 (decrease by 4)
- However, from 73 to 71, the decrease is only by 2 (not 4), and then from 71 to 63, it decreases by 8.

3. **Identify the Anomaly:**
- The expected pattern suggests that after 73, the next difference should be 69 (73 - 4 = 69).
- If we add 69 to 323, we should get:
- 323 + 69 = 392
- However, the next number in the series is 394, which is incorrect according to the established pattern.

4. **Determine the Correct Number:**
- Since 394 does not fit the pattern, we replace it with 392 to maintain the consistency of the decreasing differences.

5. **Conclusion:**
- The wrong number in the series is **394**. The correct number should be **392**.