We roll a fair 6-sided die 5 times. What is the probability that we get a 6 in at most 2 of the rolls?
P(rolling no 6's) = (5/6)^5
P(rolling one 6) = C(5,1) (1/6)(5/6)^4
P(rolling two 6's) = C(5,2) (1/6)^2 (5/6)^3
So.....the probability is
(5/6)^5 + C(5,1)(1/6)(5/6)^4 + C(5,2) (1/6)^2 (5/6)^3 = 625/648 ≈ .964 ≈ 96.4%