If n is a positive integer and 10^n is a factor of m, what is the value of n?
Given thatm=10^n*k for some positive integer k.
(1) m is the product of the first positive 40 numbers -->m=40! -->40!=10^n*k . The number of trailing zeros of 40! is 40/5+40/25=8+1=9 (check here: everything-about-factorials-on-the-gmat-85592.html). So, 40! ends with 9 zeros, which
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Given thatm=10^n*k for some positive integer k.
(1) m is the product of the first positive 40 numbers -->m=40! -->40!=10^n*k . The number of trailing zeros of 40! is 40/5+40/25=8+1=9 (check here: everything-about-factorials-on-the-gmat-85592.html). So, 40! ends with 9 zeros, which
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