以下是引用luckier在2006-3-25 10:37:00的发言: 条件概率题:
a company has 255 employees. If one employee is randomly selected, is the probability that the employee is a woman and has a college degree less than 1/2?
a) 135 employees do not (原题就在not下划了道线) have colleage degree
b) 125 employees are man
为何选A,感觉条件不够,请大牛指点,谢谢。
选A没错
题目问的a woman and has a college degree,现在条件一已经说了135个人do not have degree,题目里交待共有255个人,剩下的人中have degree只有120个人,即便全部是woman,其概率也是less 1/2,单独充分;条件二因为不知道拥有学历的人数,所以可能会出现两种结果
PS,这个题记得之前已经有G友单独提出来问过,楼主可以用搜索功能试下下
祝您好运!
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