设随机变量X~N(5,10^2),求P(X>10),P(-10

问题描述:

设随机变量X~N(5,10^2),求P(X>10),P(-10

由X~N(5,10^2),得 [(X-5)/10]~N(0,1)
P(X>10)=P{[(X-5)/10]>0.5}=1-Ф(0.5)=0.3085
P(-10