概率统计题!急A detailed analysis of your credit-worthiness shows that t_英语解答

概率统计题!急
A detailed analysis of your credit-worthiness shows that there is a 30% chance of
company A approving your credit-card application,and a 20% chance of company B
approving it,and a 50% chance that both companies will approve it.What are
the chances that at least one of these companies will approve your application?Explain.

人气：180 ℃　时间：2020-04-21 12:34:35

解答

P(A)=0.3
P(B)=0.5
P(A and B)=0.5
P(at least one)=P(A or B)=P(A)+P(B)-P(A and B)=0.3
但是这道题题目貌似出错了.因为P(B)=P(A and B)