Find the number of zeroes in 155!
(A) 30
(B) 38
(C) 42
(D) 44


Answer: (B)

Explanation: Multiplication of 2×5 results into 10. So number of zeroes depend on the number of pairs of 2 and 5.
In any factorial, number of 5’s is lesser than the number of 2’s. So, we need to count the maximum power of 5 in 155!
[155/5] + [155/5²] + [155/5³]
=31 + 6 +1
=38
Hence, number of zeroes is 38.

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