(a) Andrei flips a coin over and over again until he gets a tail followed by a head, then he quits. What is the expected number of coin flips?
(b) Bela flips a fair coin over and over again until she gets two tails in a row, then she quits. What is the expected number of coin flips?
Hello, I have been having some trouble with this problem. I have tried to use state diagrams, but bonked my head on the table, because obviously, that wouldn't work. I have not yet been able to find any method in doing this. Any help is appreciated