Multiple choice

In the following number series, a wrong number is given. Find out that wrong number. 1 5 19 73 315 1621

  1. 5

  2. 73

  3. 315

  4. 1

  5. 1621
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C Correct answer
Explanation

Analyzing the pattern: 5 = 4×1 + 1, 19 = 4×5 - 1, 73 = 4×19 - 3. The pattern appears to be: multiply previous term by 4, then subtract consecutive odd numbers (1, 3, 5, 7, ...). Following this pattern: 73×4 - 5 = 292 - 5 = 287. However, the series shows 315, which breaks the pattern. The correct number after 73 should be 287, making 315 the wrong number in the series.

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