Petra Kvitova of the Czech Republic won the 2014 Wimbledon Ladies’ Singles Championship. In the final game against Eugenie Bouchard of Canada she had 41 first serves, of which 28 were good, and three double faults.
a. Find the probability that her first serve is good.
b. Find the conditional probability of double faulting, given that her first serve resulted in a fault.
c. On what percentage of her service points does she double fault?