请教PrepMath1题，加疑问，谢谢，急！

clearguan

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上面这题我蒙的，求解题思路，谢谢呢

我昨天昨了第一套prep，错了8个题，还能给我50，这对么？不是晃点我呢吧？

恳请指点！

clearguan

咋看不清呢？我type一遍再！

last month 15 homes were sold in town A.The Average sale price of the home was 15万,and the median sale price was 13万。Which of the following statements must be true?

I At least one of the homes was sold for more than 16.5万

II At least one of the homes was sold for more than 13万 and less than 15万

III At least one of the homes was sold for less than 13万

A I only

B II only

C III only

D I & II

E I & III

ans I

clearguan

擦汗，呼唤帮助助助助助助！！！

thomasyao

III is not necessary correct.

Think: if 8 hourses out of 15 were sold at the price of 130,000. The mean value would still be $130,000

clearguan

average是15，total就是225，median是13（第8个bouse的价格）

假设前八个都是13，则13*8=104,后面7个就是121，后7个平均就是17，I At least one of the homes was sold for more than 16.5万，大概这么理解这个意思对么？

II 和 III 也有可能但不一定must be true

是这样么？

thomasyao

Yep. You made it.

clearguan

Thank you!