已知随机变量X的分布列为：p(X=k)=12k，k=1,2,3, ....，则p(2<X≤4)=（）_刷题宝

题干

已知随机变量X的分布列为：p(X=k)=

1

2

k

，k=1,2,3, ....，则p(2<X≤4)=（）

A： $\frac{3}{16}$

B： $\frac{1}{4}$

C： $\frac{1}{16}$

D： $\frac{5}{16}$

上一题下一题 0.0难度选择题更新时间:2019-07-20 10:02:20

答案(点此获取答案解析）

A

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