Question

Charles claims that he can distinguish between beer and ale 71% of the time. Ruth claims that he just guesses. To settle this, a bet is made. Charles is to be given 10 small glasses, each having been filled with either beer or ale. Charles wins if he gets 7

or more correct.

First, what is the probability that Charles makes exactly 7

correct guesses if his chance of success on a single trial is 71

What is the probability that Charles wins the bet (he makes at least 7

correct guesses)?

Answer 1