标题: 帮忙看看吧 救救我吧 简单逻辑一道 [打印本页] 作者: guo573874201 时间: 2011-9-19 11:04 标题: 帮忙看看吧 救救我吧 简单逻辑一道 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.答案居然选E 为什么呢 明明是fact2的相反的呀 不应该对呀 说的意思一样 但是就是一个大于95 一个小于95 我是怎么错了呢作者: sunnycc 时间: 2011-9-19 11:19
患Asthma的人中有95%也患HAY FEVER，但因为HAY FEVER比Asthma常见，所以患HAY FEVER的人中肯定少于95%的人也患Asthma作者: chixiaozhu123 时间: 2011-9-19 11:20
因为hay fever的人比asthma的人多 而asthma的人中友有95%是hay fever 那么肯定hay fever中有 asthma的人不到95% 我没有看明白这些单词是什么意思，但是不影响做题的 就好比一个大圆一个小圆，有交集，小圆是asthma，大圆是hay fever 两圆的交集占了小圆面积的95%，肯定这个交集就占不到大圆面积的95%了，肯定比95%小了作者: lmylove 时间: 2011-9-19 11:24
不知这样理解对不对：fact1 说A 病不如 HF常见，也就是得A 病的人数小于hay fever，fact2说得A病的人中95%会得HF。E选项和fact2 的范围不同，E选项是得HF的人又得A病的比率，而fact2 是在A病的人群中得HF的比率，由于A病概率小于HF，也就是得HF的人比得A病的人要多，由此，两者由于范围不同，所以比较的基数上E选项要更大，因为E选项是以HF的患病人数作为基数进行比较的，因此一定小于95%。