Directions (61-65) : Find the wrong number in following number series.

12 , 72 , 360 , 1440 , 4330 , 8640, 8640

The correct answer is 4330.

To find the wrong number in the given number series, let us analyze the pattern or relationship between consecutive terms:

12 , 72 , 360 , 1440 , 4330 , 8640 , 8640

Let us evaluate the operation connecting each term to the next term:

First term to second term:
$12\times 6=72$

Second term to third term:
$72\times 5=360$

Third term to fourth term:
$360\times 4=1440$

Following this pattern, the multipliers are decreasing by 1 at each step (×6, ×5, ×4, ×3, ×2, ×1).

Therefore, the fifth term should be:
$1440\times 3=4320$

Let us check the rest of the series using 4320:
Fifth term to sixth term:
$4320\times 2=8640$

Sixth term to seventh term:
$8640\times 1=8640$

All subsequent terms match perfectly when the fifth term is 4320. Thus, the number given as 4330 in the series is incorrect and should be replaced by 4320.