The 2004 Men's Champion in the Wimbledon Tennis Tournament was Roger Federer of Switzerland. During the tournament, he made of his first saves. So, he faulted on the first of the time. Given that he made a fault with his first save, he made a fault on his second serve only of the time. Assuming these are typical of his perfromance, when he serves, what is the probability that he makes a double fault?



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