设随机事件A、B满足P(A)=0.4 P(B|A)=0.3,P(A|B)=0.6 则(A ∪ B)=
问题描述:
设随机事件A、B满足P(A)=0.4 P(B|A)=0.3,P(A|B)=0.6 则(A ∪ B)=
答
P(AB)=P(B|A)P(A)=0.3×0.4=0.12
P(B)=P(AB)/P(A|B)=0.12/0.6=0.2
P(A ∪ B)=P(A)+P(B)-P(AB)=0.4+0.2-0.12=0.48