问到Prep-PS-188

artemis

188.       
Last month 15 homes were sold in Town X.  The average (arithmetic mean) sale price of the homes was $150,000 and the median sale price was $130,000.  Which of the following statements must be true?
   

(A) I only
(B) II only
(C) III only
(D) I and II
(E) I and III

答案是 A

能不能帮忙解释下。。。。thx

caicainiao

选A，那我选错了，呵呵帮不了你了

蜂鸣

回复 1# artemis


    假设最坏的情况是 前8个都是130000的话 后面7个的平均数是17****
也就是说后面7个肯定有一些数十大于17**** 或者等于 所以

artemis

回复 3# 蜂鸣


    感谢蜂鸣，我懂了

artemis

回复 2# caicainiao


    真是可爱的人