L04.8 Each Person Gets An Ace
We will now apply our multinomial formula for counting the number of partitions to solve the following probability problem. We have a standard 52-card deck, which we deal to four persons. Each person gets 13 cards as, for example, in bridge. What is the probability that each person gets exactly one ace? Well, before we start, as always we will need a probability model. We deal the cards fairly, and this is going to be our model. But we still need to interpret our statement. To give this interpretation, let us first think of the outcomes of the experiment. What are the possible outcomes? An outcome of this experiment is a partition of the 52 cards into the four persons so that each person gets exactly 13 cards. Our statement about dealing the cards fairly will be an assumption that all partitions are equally likely. So since all partitions, all outcomes of the experiment, are equally likely, this means that we can solve a probability question by counting. We need to count ...