请教数学几经--ABC三个分类中有重合的概率问题

zhujulie

There are 1,200 respondents in a survey. And they are divided into three groups, such as A, B and C with percentage of 54%, 36% and 42%(数字抄的梦飞翔的，感觉好像有点出入) respectively (numbers may not be accurate). The percentage of A and B is 30%, what is the maximum number of C that is neither in A nor B.
        我选的312，比较确定，算了两遍。

这道题似乎讨论过 但是搜索不到

我做下来感觉最大应该是1200 * （42+54+36-30-100）%。

请教题中答案是如何得到的？

多谢

zhujulie

哪位NN给点意见阿  很纠结