7. A set of 200 people, consisting of 100 men and 100 women, is randomly
divided into 100 pairs of 2 persons in each pair. Let X1 be a random variable
whose value is 1 when man i is paired with a woman, otherwise is value is zero.
No score would be given unless the calculation procedure is shown.
(a) What is E[Xi] ?
(b) What is E[XiXj] for i不等於j
想問一下這題的b小題答案是 (100*99) / (199*197) 嗎
看過兩本解答本都寫這個答案 但是有一本是寫成 (100*99) / (2*199*197)
不知道哪個答案才是對的 想請教一下各位大大 感謝
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