Jane Street

Interview Question

Assistant Trader Interview
Jane Street

You have 100 green marbles and 100 red marbles and can divide them however you like between two bags, with at least one marble in each bag. A player, who does not know the distribution, randomly chooses one of the bags and draws a single marble. If the marble is green, the player wins $100; if red, they win nothing. What is the fair price for this game?

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