Four people play the game Flipper described in the link above. They decide to play on an elimination basis, namely the two winners of the first round games play each other in the second to establish an overall winner. Lots are drawn to decide who plays who in the first round.

Each player has a coin of value X, and each has a second coin valued A, B, C, and D, respectively.

(a) If X > A > B > C > D, what is each player's probability of being the overall winner?
(b) If the probability of each player being the overall winner is proportional the value of the two coins, and if A is prime, what are the values of X, A, B, C and D?