数学 jj 下午考 麻烦大家帮忙

ylvachaochao

38. A financial investment club has *A* members with investment either in bond or in stocks. *B* don't invest in either of them. *C* invest in stock. *D* invest in bond. hnow many people invest in both?

B是不是没用的条件呢？

dianecarton

恩

[此贴子已经被作者于2008-9-11 21:52:24编辑过]

ynl06

是的吧