请教DS

Carrie2009

During a sale, a clothing store sold each shirt at a price of $15 and each sweater at a price of $25. Did the store sell more sweaters than shirts during the sale?

1)The average(arithmetic mean) of the price of all of the shirts and sweaters that the store sold during the sale was $21

2)The total of the price of all of the shirts and sweaters that the store sold during the sale was $420
答案A。为什么不是D？Statement（2）有什么快点的方法吗？一个一个试的话会很慢。。。

killer1294

因为如果sweater和shirt卖的一样好的话，average应该是20，而a条件给出的average是21，所以一定是卖的贵的sweater多一些

Carrie2009

因为如果sweater和shirt卖的一样好的话，average应该是20，而a条件给出的average是21，所以一定是卖的贵的sweater多一些

-- by 会员 killer1294 (2010/10/2 16:41:38)

但是Statement（2）怎么判断呢？

Carrie2009

有童鞋会吗？