问PREP　math 2-192 答案没问题吗？快考试了

diana1228cn · 发表于 2007-8-21 16:53:00

PREP2-192 math

Of the 75 houses in a certain community, 48 have a patio. How many of the houses in the community have a swimming pool?

(1) 38 of the houses in the community have a patio but do not have a swimming pool.

(2) The number of houses in the community that have a patio and a swimming pool is equal to the number of houses in the community that have neither a swimming pool nor a patio.

答案给的ｂ

我选的ｃ

实在是想不通，就在条件ｂ里，一个式子怎么能解二元方程？？

快考试了，麻烦大家指教～～

dirtycircle · 发表于 2007-8-21 17:05:00

我找不到这题。。。是不是你答案看错了？

diana1228cn · 发表于 2007-8-21 21:16:00

答案没有错，刚刚又核对了一遍。

不过题号不好意思表错了

是PREP MATH DS 1-192 答案是ｂ

nuj_am · 发表于 2007-8-21 22:32:00

是可以的，楼主画画图就知道了，假设x是有游泳池的，那么75-（48+x）等于什么呢？？

等于啥也没有的这部分人和什么都有的那部分人的和，对不对？

然后2说这两部分人相同，那不就是答案了？

问PREP　math 2-192 答案没问题吗？快考试了