Please Help!!!

A pair of dice are rolled and the sum on their upturned faces is recorded. WHat is the probability that the sum showing is 8, given that one dice is showing a 5?

1 answer

When one AND ONLY ONE die shows a five, the other die can show 1 through 6 with equal probability. However, the possibility of a 5 is excluded becasue you have said that only one die had a five. You are asking for the probability of throwing a 3 with the "other" die. That is 1/5, for outcomes with only one five showing.