#2**+2 **

How many of the factorials from 1! to 100! are divisible by 9?

9! up to 100! all have 9 as one of the factors. so that is 100-9+1=92 (assuming 100! id included)

6! = 1*2*3*4*5*6 = 2*4*5*18 = 2*4*5*2*9

so 6!, and above all have 9 as a factor, so I will include 6!, 7!, and 8! 92+3=95 so far.

5!=1*2*3*4*5 9 is not a factor.

**So 95 of them have 9 as a factor**

Melody Feb 12, 2018