帮忙看一下这道MATH JJ

yxydsy2007

忙帮忙看一下

58.   100 students take A, B, C courses. Student take A+B+C=80, while 10 take AB, 18 take AC, 12 take BC, and 9 take ABC, how many students do not take any courses at all?

不用了，知道怎么算了

[此贴子已经被作者于2008-1-30 1:31:53编辑过]