document.write( "Question 1203262: Roger and Andy play a tennis match in which the first person to win two sets wins the match. The probability that Roger wins the first set is 0.6. For sets after the first, the probability that Roger wins the set is 0.7 if he won the previous set, and is 0.25 if he lost the previous set. No set is drawn.
\n" ); document.write( "(i) Find the probability that there is a winner of the match after exactly two sets.
\n" ); document.write( "(il) Find the probability that Andy wins the match given that there is a winner of the match after
\n" ); document.write( "exactly two sets.
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Algebra.Com's Answer #838687 by Edwin McCravy(20063)\"\" \"About 
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\n" ); document.write( "(i) Find the probability that there is a winner of the match after exactly two
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\n" ); document.write( "\n" ); document.write( "P(RR or AA) = P(RR or R'R') = P(RR) + P(R'R') = (0.6)(0.7) + (1-0.6)(1-0.25) =\r
\n" ); document.write( "\n" ); document.write( "0.42 +(0.4)(0.75) = 0.42 + 0.3\r
\n" ); document.write( "\n" ); document.write( "(il) Find the probability that Andy wins the match given that there is a winner of
\n" ); document.write( "the match after exactly two sets.\r
\n" ); document.write( "\n" ); document.write( "P[AA | (RR or AA)] = P[AA and (RR or AA)]/P(RR or AA) = P(AA)/0.72 = 0.3/0.72 =
\n" ); document.write( "30/72 = 5/12\r
\n" ); document.write( "\n" ); document.write( "Edwin

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