GWD-9-Q13

easylau · 发表于 2007-7-21 10:41:00

GWD-9-Q13: E

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?

Hay fever is a prerequisite for the development of asthma
Asthma is a prerequisite for the development of hay fever
Those who have neither hay fever nor asthma comprise less than 5 percent of the total population
The number of people who have both of these ailments is greater than the number of people who have only one of them
The percentage of people suffering from hay fever who also have asthma is lower than 95 percent.

哪位能帮我解说一下吗？偶脑子转不过来了

allfar · 发表于 2007-7-21 14:21:00

转化为数学题目～

AB首先排出；无关。

C因为总百分比不清除，也推不出来。

D也不能推出。因为hay fever可能100%在asthma中。

[此贴子已经被作者于2007-7-22 14:41:13编辑过]

easylau · 发表于 2007-7-21 14:35:00

答案不是E么？

easylau · 发表于 2007-7-22 11:26:00

这题答案到底是什么？

addy · 发表于 2007-7-22 11:51:00

答案是E

n个A病人中患有HF的超过95%,因此患有A且患有HF的病人人数大于95%n

由于患A病的人比患HF病的人少( Asthma is much less common ailment than hay fever),假设患HF病的有x个人,那么n<x

==>(95%n)/x<95%

[此贴子已经被作者于2007-7-22 11:52:05编辑过]

addy · 发表于 2007-7-22 11:54:00

其实就是那个基数变化了呵呵

easylau · 发表于 2007-7-22 12:18:00

说的真明白！

多谢

crazy6025 · 发表于 2007-7-22 12:33:00

选择E对不对？

easylau · 发表于 2007-7-22 12:38:00

对的，是E

fangrong · 发表于 2008-4-6 03:58:00

"Much less common" is a key point to get "must true" answer-E.