请教GWD31--1--19

seuhongkai

A total of $60,000 was invested for one year.  But of this amount earned simple annual interest at the rate of x percent per year, and the rest earned simple annual interest at the rate of y percent per year.  If the total interest earned by the $60,000 for that year was $4,080, what is the value of x?
(1)      x = (3/4) y
(2)    The ratio of the amount that earned interest at the rate of x percent per year to the amount that earned interest at the rate of y percent per year was 3 to 2.
请教大侠们，实在很难理解为啥要选C

mudiduanger

顶起来！！！我也想知道！！！

MarilynR

是选C没错~
题目的意思就是60000分两部分存，一部分设a元，用x利率；另一部分就是(60000-a)用y利率，最后一年利息所得是4080。问求x.
用条件一得到xy的关系；用条件二得到a的值，只有两者结合才能求出x。

这是我的思路，希望能帮到你。