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Determine the probability - ILL 1990 FIN1

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September 18, 2010
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Problem Statement

Six cities A,B,C,D,EA, B, C, D, E, and FF are located on the vertices of a regular hexagon in that order. GG is the center of the hexagon. The sides of the hexagon are the roads connecting these cities. Further more, there are roads connecting cities B,C,E,FB, C, E, F and GG, respectively. Because of raining, one or more roads maybe destroyed. The probability of the road keeping undestroyed between two consecutive cities is pp. Determine the probability of the road between cities AA and DD is undestroyed.