问题
单项选择题
In 1985 a company sold a brand of shoes to retailers for a fixed price per pair. In 1986 the number of pairs of the shoes that the company sold to retailers decreased by 20 percent, while the price per pair increased by 20 percent. If the company’s revenue from the sale of the shoes in 1986 was $3.0 million, what was the approximate revenue from the sale of the shoes in 1985 ？（）
A．$2.4 million
B．$2.9 million
C．$3.0 million
D．$3.1 million
E．$3.6 million
答案
参考答案：D
解析：
设1985年该公司共卖出鞋a双，每双鞋的单价是b美元，且1985年卖鞋的销售收入是x美元，则根据题意可得$3.1 million。