Question

You have three dice. What is the probability to find rolling two same number?

Answer 1

let's pick one specific case
e.g. two 3's and the third one different
33?
the probability of that is 1/6 * 1/6 * 5/6
but there are 3 ways for 33? to turn up
33?,3?3, and ?33

but there are 6 such cases that could happen
two 1's, two 2's etc
so the prob. is 6(1/6)(1/6)(5/6)(3) = 5/12

Answer 2

Thank you so much.