Answer: 15/28 Suppose the following: event A: the event that there were 3 sixes in the 8 roles, event B: the event that there were 2 sixes in the first 5 roles. Then the conditional probability to find is P(B|A)=P(A∩B)/P(A). P(A)=C(3,8)*(1/6)^3*(5/6)^5, P(A∩B)=C(2,5)*(1/6)^2*(5/6)^3*C(1,3)*(1/6)*(1/6)^2 ∴P(B|A)=15/28
