Suppose that a person plays a game in which his score must be one of the 5 numbers 1,2...,5 and that each of these 5numbers is equally likely to be his score. The first time he plays the game, his score is X. He then continues to play the game until he obtains another score Y such that Y大於等於X. Assuming that all plays of the game are independent. Find the probability of the event that Y = 5 答案是137/300 请帮一下 谢谢 --

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