P(B | A) =P(A∩ B) /P(A)
P(A∩ B)=0.4*0.8
=0.32
P(A∩ B) =P(A)*P(B)
P(B)=0.32/0.8
=0.4
28 若任二事件 A 與 B,已知 P{A} = 0.8和 P(B | A) =..-阿摩線上測驗