随机变量X~B(2,P),随机变量Y~B(3,P),若P(X大于等于1)=5/9,则P(Y大于等于1)=

问题描述:

随机变量X~B(2,P),随机变量Y~B(3,P),若P(X大于等于1)=5/9,则P(Y大于等于1)=

随机变量X~B(2,P),
P(X=0)=(1-P)^2,
P(X大于等于1)=1-P(X=0)
=1-(1-P)^2=5/9
(1-p)^2=4/9
1-p=2/3; p=1/3
P(Y大于等于1)=1-P(Y=0)=1-(1-P)^3=1-8/27=19/27