试题与答案

设随机变量X服从区间(-1,5)上的均匀分布,Y=3X-5,则E(Y)与D(Y)分别

题型:单项选择题

题目:

设随机变量X服从区间(-1,5)上的均匀分布,Y=3X-5,则E(Y)与D(Y)分别等于().

A.1,9

B.3,27

C.4,27

D.1,27

答案:

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