476.Fair Price per Door
★★★expected valueCh. 6 — Random Variables and Expectation444+ Problems in Probability
On a game show, sits behind each of 2 of 7 doors; the other 5 hide nothing. You open distinct doors uniformly at random until you find the first prize. If each door opening costs and the game is fair, what is ?
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The 2 prizes split the 5 empty doors into 3 gaps of equal expected size.
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