Jane Street

Interview Question

Quant Trader Interview
Jane Street

You are playing a one-player game with two opaque boxes. At each turn, you can choose to either 'place' or 'take.' 'Place' puts $1 from a third party into one box randomly, while 'take' empties out one box randomly and the money is yours. The game consists of 100 turns, and at each turn you must either place or take. Assuming optimal play, what is the expected payoff of this game? Note: You do not know how much money you have taken until the end of the game.

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