Jane Street

Interview Question

Quantitative Researcher Interview
Jane Street

You have two decks of cards: a 52-card deck (26 black, 26 red) and a 26-card deck (13 black, 13 red). You randomly draw two cards and win if both are the same color. Which deck would you prefer? What if the 26-card deck was randomly drawn from the 52-card deck? Which deck would you prefer then?

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