How many zeros are there at the end of 100!?
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How many zeros are there at the end of 100!?
I think the answer is 24.
Because you see at the end of the 5!(120) you got one zero. End of 10!(3628800) you got 2 zeros. if you calculate like this every 5 factorial and 10 factorial contailns a extra zero..
So now totally 20. After that one more conditions occurring here. Numbers 25, 50 and 75 when multiplied by some of the small numbers vailable eg (4, 2 and 6)generate an extra zero.
So totally 24 zeros...i don't this is the easiest way...if anyone have other simple solution then plz post here..
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suresh
ur answer is correct...but i have mechanical method by which u can tell no of zeros after any number's factorial
i think its 21.
Hey Smart Coder
100/5 = 20
20/5 =4
4/5 = 0
20+4 = 24 zeroes....
Thanks
Manoj:)