Question

1.已知P(A非)=0.3 P(B)=0.4 P(A不非B非)=0.5 求P(B|A∪B非)

Answer 1

1 P(a并B非)=P（A）+P（B非）-P（A不非B非）=0.7+0.6-0.5=0.8

P(ab)+P(aB非)=P(a); P(ab)=0.2

P(B|A∪B非)=P(B,A∪B非)/0.8=P(BA∪BB非)/0.8=P(BA)/0.8=1/4

2 P(A)=0,92 P(B)=0,93 P(B/-A)=0,85 P(-AB)= P(-a)P(b/-a)= 0.08*0.85=0.068 P(ab)+P(-ab)=P(b)

P(ab)=0.93-0.068=0.862

2(1) P(a+B)=P(a)+P(b) - P(ab)= 0.988

2(2) P(a/-b)=P(-ba)/P(-b)=(0.92-0.862)/0.07=0.829