(Monte Hall Problem). Suppose there are three curtains. Behind one curtain
there is a nice prize while behind the other two there are worthless prizes. A
contestant selects one curtain at random, and then Monte Hall opens one of the
other two curtains to reveal a worthless prize. Hall then expresses the
willingness to trade the curtain that the contestant has chosen for the other
curtain that has not been opened. Should the contestant switch curtains or
stick with the one that she has? If she sticks with the curtain she has then
the probability of winning the prize is \(1 / 3 .\) Hence, to answer the
question determine the probability that she wins the prize if she switches.