A betting company organized a betting game. According to the game, two marbles (one red and one blue) will be placed in a dark box and if the player picks blue marble, he will get 5000$ and if he guessed it wrong he needs to pay 100$. The company was a cheater and every they put two red balls instead of one red and one blue.
Rodrik was observing that all the players are losing the game.
Next Rodrik goes to play and won. Explain?
Rodrik picks a marble and without showing it to anyone swallows it and then picks the remaining marble and shows to everyone which was red which proved the first marble prisoner pick must be blue and hence betting company needs to pay him 5000$.