- #1
pony1983
- 5
- 0
Homework Statement
If 5 numbers are randomly generated (excluding zero) what are the odds that the product of the 5 numbers will be divisible by 9?
I realize that if at least one number is divisible by 9 then the product will also be divisible by 9 or if there's at least 2 numbers divisible by 3(that aren't divisible by 9) the product will be divisible by 9.
Homework Equations
I don't know the relevant equations.
The Attempt at a Solution
My best attempt at a solution is 1-(7/9)^4 - I feel like this would be the odds of getting at least 2 numbers that are divisible by 3 that aren't divisible by 9 and 1-(8/9)^5 I feel are the odds of getting at least 1 number divisible by 9. I don't know how to combine the 2 though.
P.S. This is not a homework problem but I felt this would be the proper forum as I believe it is a "homework style" question. Thanks for your help.