GWD-12-Q15 求助！

冬瓜

FastMart, a convenience store chain, is planning to add pancake syrup to the items it sells.  FastMart stores do not have shelf space to stock more than one variety of syrup.  Surveys of FastMart customers indicate that one-fourth of them prefer low-calorie syrup, while three-fourths prefer regular syrup.  Since FastMart’s highest priority is to maximize sales, the obvious strategy for it is to stock regular syrup.

Which of the following, if true, most seriously weakens the argument?

A.    eople buying pancake syrup at convenience stores, unlike those buying it at supermarkets, generally buy it only a few times.
B.    eople who prefer low-calorie syrup generally use about the same amount of syrup on their pancakes as those who prefer regular syrup.
C.    Regular syrup does not sell for a higher price per unit than low-calorie syrup.
D.    In general, customers who prefer regular syrup will buy low-calorie syrup if regular is unavailable, but those who prefer low-calorie will not buy regular syrup.
E.    Sales of syrup are not expected to account for a large proportion of total dollar sales at the average FastMart store.

好像没有相关问题的帖子，我怎么搜也搜不到。。。请哪位高人指点一下

hzd515976083

FastMart, a convenience store chain, is planning to add pancake syrup to the items it sells.  FastMart stores do not have shelf space to stock more than one variety of syrup.  Surveys of FastMart customers indicate that one-fourth of them prefer low-calorie syrup, while three-fourths prefer regular syrup.  Since FastMart’s highest priority is to maximize sales, the obvious strategy for it is to stock regular syrup.

Which of the following, if true, most seriously weakens the argument?

背景信息：
超市要卖syrup，只能卖一种，25%的人选低热量版，75%的人选常规版。
目标：
maximize sales销售额最大
问题：
卖哪一种呢？

A.    eople buying pancake syrup at convenience stores, unlike those buying it at supermarkets, generally buy it only a few times. （根本没有在两种syrup比较，无关项）
B.    eople who prefer low-calorie syrup generally use about the same amount of syrup on their pancakes as those who prefer regular syrup.（买低热量版的人不会一次多买一点，那么根据“购买人数*单个消费者购买量”，当然是哪种买的人多就卖哪种，应该是常规班，支持项）
C.    Regular syrup does not sell for a higher price per unit than low-calorie syrup.（常规版的价格<=低热量版的价格。其实，仅仅这一信息，既不支持，也不反对）
D.    In general, customers who prefer regular syrup will buy low-calorie syrup if regular is unavailable, but those who prefer low-calorie will not buy regular syrup.（没有常规版，人们就会买低热量版，这样所有人都会买syrup，这比卖常规版时只有75%的人会买syrup人数更多，那么这就让我们更相信卖低热量版是个好选择，驳斥项）
E.    Sales of syrup are not expected to account for a large proportion of total dollar sales at the average FastMart store.（根本没有在两种syrup比较，无关项）

所以D是正确的。其实驳斥项并不一定导致原结论的反面。比如这一题，在D成立的情况下，我们就一定能得出卖低热量版比卖常规版销售额更大么？不能。
因为，销售额=销量*单价，这里只说了销量会增加，单价呢？我们不知道。
但是，这是正确答案，因为驳斥项的只被要求让人们更相信原结论不太可能发生。
其实如果把D这样改写，就是一个支持项。
In general, customers who prefer regular syrup will buy low-calorie syrup if regular is unavailable, but those who prefer low-calorie will not buy regular syrup. However, the price for regular syrup is at least one-third more than that of low-calorie syrup.

冬瓜

谢谢，分析得很好！我也考虑到了即使D正确也有缺陷，但我weaken就是以为是100%不对了。。。导致更加混乱的思维。。。

bdsjb116

http://forum.chasedream.com/GMAT_CR/thread-74525-1-1.html 这个里面说weaken题型挺有用的

3．WEAKEN

看原文：找出结论和推出该结论的前提。特别注意结论的特殊性和具体性。

找答案：用结论的具体性去区分有关无关，并结合TEST。对于特殊类，先预测出答案，用此预测去找答案

TEST：问自己，是否该答案使作者再考虑他的观点或迫使作者做出反应或原文该前提能证明该结论吗。

几种特殊类型：

原文前提和结论关系不密切：正确选项直接WEAKEN结论

因果型结论：即原文给出两件事，然后得出结论说是一件事（因）导致另一件事（果）。WEAKEN该结论的方法包括：A。是其他原因或可能导致该结果。B。割断因果：或有因无果或有果无因。C。因果颠倒了。D显示因果关系的资料不准确。

条件型结论：结论带条件（即为充分必要）。WEAKEN的方法显示充分条件成立，必要条件可以不成立。或举反例，或提供有关信息。

原文是类比：WEAKEN方式为两者本质不同

调查：有效性受怀疑（被调查的没代表性等）


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现在只要看到weaken题就问自己是否该答案使作者再考虑他的观点或迫使作者做出反应或原文该前提能证明该结论吗。

liran95

C 选项说明low的单价比普通的单价高，不能说明单个的利润就高么？

lingxi1023

我觉得C也可以啊 为什么不行呢

say22

设R单价=3   L单价=5   total=100人 R的人数=75人  L的人数=25人
R的获利=3*75=$225
L的获利=5*25=$125  R的获利($225)> L的获利($125)
支持前提(卖R  -->获利?)
假设可以找到一组解是R获利=L获利或是R获利<L获利
?-->C这个选项是有缺陷的，不能选

say22

D选项:?  
买R的人，因为没卖R-->买L
   
买L的人，没L不会买R

假设超商只卖R?四分之三的人买(因为四分之一买L的人不会买)
       超卖只卖L?全部买糖浆的人都会买=1
?     1(卖L)>3/4(卖R)
?      同因生反果(weaken)