Two teams are in a best-two-out-of-three playoff: the teams will play at most games, and the winner of the playoff is the first team to win games. The first game is played on Team A's home field, and the remaining games are played on Team B's home field. Team A has a chance of winning at home, and its probability of winning when playing away from home is . Outcomes of the games are independent. The probability that Team A wins the playoff is . Then can be written in the form , where and are positive integers. What is ?
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