# Inclusion Exclusion Dice Problem

• August 28th 2009, 04:07 PM
morganfor
Inclusion Exclusion Dice Problem
What is the probabililty if you throw six dice, at least one number will appear exactly once?

I know it involves the inclusion exclusion principle but i'm still confused about how to solve it
• August 30th 2009, 02:07 AM
DaRush19
Did you find an answer to this? I'm stuck on the same question (Worried)
• August 30th 2009, 05:42 AM
pedrosorio
Consider Ai to be the set of dice rolls that have number i appearing exactly once.

You want to find $\frac{\left|\begin{array}{c}6\\\bigcup\\i=1\end{ar ray} A_i\right|}{\left|\mbox{The set of all possible dice rolls}\right|}$

Apply the inclusion-exclusion principle to find $\left|\begin{array}{c}6\\\bigcup\\i=1\end{array} A_i\right|$

Inclusion-exclusion principle - Wikipedia, the free encyclopedia