Answer to Question #26808 in Statistics and Probability for Abhinav

Question

What is the probability of rolling exactly two sixes in 6 rolls of a die?

Solution by Binomial Probability function is
(6C2)*((1/6)^2)*((5/6)^4) = (15*((5)^2))/(6^6)

But by basic probability understanding
Probability = successful outcome/ total possible out come
So that way the probability should be 15/ (6^6)

I know that second calculation is giving the right answer, but some how not convinced on why it is wrong as I don’t see approach being wrong.


Can someone help me understand why second approach is wrong?