SOLUTION: what is the last non zero digit of 96! ?

Algebra ->  Exponents -> SOLUTION: what is the last non zero digit of 96! ?      Log On


   

Question 104236: what is the last non zero digit of 96! ?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
The factorial n! is defined for a positive integer n as

n%21 = n%28n-1%29%28n-2%29………2%2A1
as you can see, the last non-zero digit is 1.
so
96%21 = 96%2A95%2A94....2%2A1
the last non-zero digit is 1