Expert: Sherry Wallin - 4/22/2010

Question
Using five standard dice, I roll the dice looking for sixes.  Each six rolled is set-aside, and the remaining dice are rolled a second time, again looking for sixes.  The sixes are set aside and the remaining dice are rolled a third time.  What is the probability of rollings at least three sixes?

Answer
There are 5 dies and there is a probability associated with each die on each roll. For each die there is a chance that the die will be a six 1/6 of the time. This is true for all 5 dies or (1/6)^5 which is the probability that all five dies are 6's. On the next roll you don't know how many 6's you rolled the first time and you aren't given that they are replaced so you really can't answer this question. But depending on mhow many sixes you made in the first roll it would be:
(1/6)^(5 - #in previous roll)

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