Question

Two six sided dice are rolled. What is the probability of one of those being a 4?

Answer 1

P(4)=1/6
P(not 4)=5/6
n=2 p=1/6 q=5/6
P(X=1)=2C1*(1/6)*(5/6)*=5/18
ans:5/18

or list down all the sample space
i only list down getting a 4
{(1,4),(2,4),(3,4),(5,4),(6,4),(4,1),(4,2),(4,3),(4,5),(4,6)}
P(getting a 4)=10/36=5/18