I figure I'm missing something extremely obvious in this question but I cannot get the answer the book says!
Chapter 18 Probability Revision Extended Response question 3c part i in the Methods (Non CAS) Essentials book.
Lleyton Hewitt and Roger Federer are playing the final of a tennis tournament. The winner of the match will be the first player to win two sets. The results of each set follows a Markov sequence, as described below
Pr(L1) = 0.45
Pr(R1) = 0.55
Pr(Li+1|Li) = 0.6
Pr(Ri+1|Li) = 0.4
Pr(Li+1|Ri) = 0.45
Pr(Ri+1|Ri) = 0.55
What is the probability that Lleyton Hewitt will win the match given that he wins the first set?
By my logic, this leaves two possible outcomes:
Leyton wins the next game.
Pr(Li+1|Li)
Roger wins the next game, Lleyton wins the one after that.
Pr(Ri+1|Li) x Pr(Li+1|Ri)
The combined probability of these two possible outcomes would then be
Pr(Li+1|Li) + [Pr(Ri+1|Li) x Pr(Li+1|Ri)]
= 0.6 + (0.4 x 0.45)
= 0.78
The answer in the back of the book says 0.6
What am I missing here?