【已刪除】 -阿摩線上測驗
1F meimei 高三下 (2015/02/11)
(A)p(A∪B)=p(A)+p(B)-p(A∩B),所以(7/12)=(1/2)+(1/3)-p(A∩B),得-p(A∩B)=3/12=1/4......正確 (B)p(A|B)=p(A∩B)/p(B)=(1/4)/(1/3)=3/4......正確
(C)p(B|A)=p(A∩B)/p(A)=(1/4)/(1/2)=1/2
(D)p(A')=1/2, p(B')=2/3,p(A'∩B')=5/12,所以p(A'|B')=p(A'∩B')/p(B')=(5/12)/(2/3)=5/8
(E)p(B'|A')=p(A'∩B')/p(A')=(5/12)/(1/2)=5/6......正確 |