不公平得分：应选多少局

A game consists of a sequence of plays; on each play either you or your opponent scores a point, you with probability $p$ (less than $\frac{1}{2}$ ), he with probability $1 - p$ . The number of plays is to be even - 2 or 4 or 6 and so on. To win the game you must get more than half the points. You know $p$ , say 0.45 , and you get a prize if you win. You get to choose in advance the number of plays. How many do you choose? Matching Problems (45 and 46)