P( no fives) = (5/6)^9
P( 1 five) = C(9,1)(1/6)(/6)^8
P(2 fives) = C(9,2) ( 1/6)^2 ( 5/6)^7
P(3 fives) = C(9,3) (1/6)^3(5/6)^6
P(4 fives) = C(9,4)(1/6)^(4)(5/6)^5
So....the probability is just the sum of these
(5/6)^9 + C(9,1)(1/6)(5/6)^8 + C(9,2)(1/6)^2 (5/6)^7 + C(9, 3)(1/6)^3(5/6)^6 + C(9, 4) (1/6)^4 (5/6)^5
≈ .99 ≈ 99%