08.Smallest Card Beside the Hundred
★★★expected valueJane Street
Cards numbered 1 to 100 are dealt one at a time into two boxes: for each card a fair coin decides whether it goes left or right. Consider the box that ends up holding card 100. What is the expected value of the smallest card in that box?
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Use the tail formula. The minimum exceeds m only when cards 1 through m all landed in the other box.
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