Question

概率论与数理统计设A,B,C是随机事件，A,C互不相容，P(AB)=1/2,P(C)=1/3，求P(AB/-C)=？详细

Answer 1

P(AC)=0

P(ABC)=0

P(AB)=P(AB(C+(-C))=P(ABC)+P(AB(-C))=P(AB(-C))=P(AB|-C)P(-C)

P(AB|-C)=P(AB)/P(-C)=(1/2)/[1-(1/3)]=3/4