GMAT
题目
Sam earned a $2,000 commission on a big sale, raising his average commission by $100. If Sam's new average commission is $900, how many sales has he made?
解析
另一种解法：
设之前的总销量为\(s\)
则总收益 = \(800s\)
新的平均收益\(900 = \frac{800s + 2000}{s+1}\)
求解得：\(s = 11\)
总销量 = \(11 + 1\)（新增销量）= 12（答案）
在线客服
官方微信
公众号