题目内容
设随机变量X~N(1,52),且P(X≤0)=P(X>a-2),则实数a的值为
A.10
B.6
C.8
D.4
A.4 B.2 C. D.1
设随机变量X-N(1,22),则D(X)等于
4
2
1
设随机变量X~N(1,32),且P(X≤0)=P(X>a-6),则实数a的值为________.
A.4 B.2 C. D.1