maths
posted by adex on .
A fair die is rolled three times. Find the chance that three different faces appear.

on the first roll, some face appears.
On the 2nd roll, there's a 5/6 chance that a new face appears
On the 3rd roll, there's a 4/6 chance that a new face appears.
So, p=(1)(5/6)(4/6) = 5/9