7-此题具让我恶心

gansen

169是哪？

gansen

不懂。
算了，哪儿都一样！
我本来是十月十一号考的，一来怕没什么机经，而来十月中考托福，想多点时间准备，就提前了。
加油哦！

tongxun

167与广外是两个不同的地方。

steven.wei

a camera with 5 filters,the total price sell 57.5$,if we purchase separately ,each of the two of the filters is 10.45$,each of the another is 12.05$.the last one is 17.5,what is the percentage the saving when we buy it as a whole of the cost when we buy separately.
ans:2/25
[讨论](10.45*2+12.05*2+17.5)=62.5
(62.5-57.5)/62.5

此题具让我恶心。其实不难，但就是不知道是“(62.5-57.5)/62.5”还是“(62.5-57.5)/57.5”，并且我敢说ETS肯定两个答案都放上。到底应该除谁，让我忧愁的一道题。

tongxun

(62.5-57.5)/62.5