Rank: ? (171)
Member #: 11947

How many zeros are at the end of 1,097,324,659! w/out actaully calculating the factorial?

(answer posted in 3 days, i think that should be enough )

Rank: ? (171)
Member #: 11947

nobody!??

Ok a hint:

1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10...

now... a number times a number ending in zero will result in a zero added to the end of the number:

2*5 & 10

so any number ending in 5 (2 is below five, so we'll use upper bound)
and any number ending in 0... (make sure ot count multiple zeroes!!)