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First ace, with replacement or without

Asked at Jane Street

You draw cards from a standard 5252-card deck looking for the first ace, one draw at a time.

Compare the expected number of draws to the first ace when you draw without replacement (an ordinary shuffle) versus with replacement (reshuffle after each draw).

Show a hint

Without replacement, use the gap/symmetry argument. With replacement, each draw is an independent trial, so the waiting time is geometric.

Your answer

This one is open-ended. Work it through, then check your reasoning against the full solution.

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