[商管] [統計]-機率分配
Two coins are simultaneously tossed until one of them comes up a head
and the other a tail. The first coin comes up a head with probability 1/3
and the second with probability 1/2. All tosses are assumed independent.
Let X be the number of tosses until the game is over.
1. Find the expected value and the variance of X
2. Given that X is greater than 3, what is the conditional probability
that X is greater than 5 ?
請問這題要用甚麼方向去想呢?
本來是想說開離散的機率表
但是似乎又不大對
麻煩板上高手指點迷津
謝謝
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03/04 11:45, , 1F
03/04 11:45, 1F
※ 編輯: hidmey 來自: 114.137.230.94 (03/04 12:35)
※ 編輯: hidmey 來自: 114.137.230.94 (03/04 12:37)
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