题意是：每条领带降价20%,每条皮带降价30%
问一条领带和两条皮带的总降价百分比与25%的大小比较
答案就是无法比较,因为不知道领带和皮带各自的价格
如果要算总降价百分比,需要用各自降价百分比乘以各自价格再除以总价格
这就是所谓的加权平均,而没有单价是无法进行加权平均的
所以就是无法比较
我的解答更详尽一些,纯手打,
一道GRE数学题,
一道GRE数学题,
At a sale,the cost of each tie was reduced by 20 percent and the cost of each belt was reduced by 30 percent.
比较
The percent reduction on the total cost of 1 tie and 2 belts
和
25%
答案是无法比较.
At a sale,the cost of each tie was reduced by 20 percent and the cost of each belt was reduced by 30 percent.
比较
The percent reduction on the total cost of 1 tie and 2 belts
和
25%
答案是无法比较.
数学人气：626 ℃时间：2020-04-23 11:18:22
优质解答
我来回答
类似推荐