how many zeros at the end of factorial 25??
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Number of zeros is identified by number of 10s that 25! can be divided by
10 = 2*5
So, we just have to look at how many pairs of 2 and 5 can we make in factors of 25!
As 2s are abundant in 25!: 2, 4, 6, 8, 10 … 24
% would be the limiting factor and we simply look at the number of 5s:
5 - 1
10 - 1
15 - 1
20 - 1
25 - 2
Total number of 5s in the prime factorisation of 25! = 1+1+1+1+2 = 6
These six 5s can be multiplied with six 2s and give six 10s
Therefore, the answer would be 6 zeros
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thnks
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by error
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