国际顶尖MBA申请交流平台--TOPWAY MBA

标题: GWD-18-Q15 [打印本页]

作者: thumbbunny 时间: 2012-6-8 07:02 标题: GWD-18-Q15

Fact:
Asthma, a bronchial condition, is much less common ailment than hay fever, an allergic inflammation of the nasal passages.

Fact:
Over 95 percent of people who have asthma also suffer from hay fever.

If the information given as facts above is true, which of the following must also be true?

A.
Hay fever is a prerequisite for the development of asthma.

B.
Asthma is a prerequisite for the development of hay fever.

C.
Those who have neither hay fever nor asthma comprise less than 5 percent of the total population.

D.
The number of people who have both of these ailments is greater than the number of people who have only one of them.

E.
The percentage of people suffering from hay fever who also have asthma is lower than 95 percent.

请问下NN，为什么选择E，为什么排除CD？用韦恩图可以解决吗？

作者: IESE 时间: 2012-6-8 21:58

看了这个解释泪奔了，也就是第二个fact就是拿来糊弄人的啊！明显不可能哈！
其实这题可以用概率论的知识推导出来的：
条件1：P（A）<P(B)
条件2：P（B/A)（也就是在A发生的前提条件下，B发生的概率）=P(AB)除以P（A）=0.95
而E选项是求P（A/B)=P(AB）除以P(B)
由于P(A)<P(B),所以E选项小于0.95

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