In a certain medical survey, 45 percent of the people surveyed had the type ~$A$~ antigen in their blood and 3 percent had both the type ~$A$~antigen and the type ~$B$~ antigen. Which of the following is closest to the percent of those with the type ~$A$~ antigen who also had the type ~$B$~ antigen?
1.35%
6.67%
13.50%
15.00%
42.00%
没看懂问的啥
木有看懂题目。。。
mark,
不是数学不好,是语言不好!!问的是:有A里的人里,有B的比例。3%/45%