[求助]og-46

timothyyung

og-46

46.

Kale has more nutritional value than spinach. But since collard greens have more nutritional value than lettuce, if follows that kale has more nutritional value than lettuce.



Any of the following, if introduced into the argument as an additional premise, makes the argument above logically correct EXCEPT:



A. Collard greens have more nutritional value than kale

B. Spinach has more nutritional value than lettuce

C. Spinach has more nutritional value than collard greens

D. Spinach and collard greens have the same nutritional value

E. Kale and collard greens have the same nutritional value

答案为A，本人对OG解释有异议，且感觉全部5个选项都支持结论。

我的推导步骤，请指出错误：

Evidence:

Kale has more nutritional value than spinach.  （K >S)

But since collard greens have more nutritional value than lettuce(C>L)

conclusion:

if (i think it should be "it")follows that kale has more nutritional value than lettuce. (K>L)

A: Collard greens have more nutritional value than kale (C>K)

if C=6,K=5,S=4,L=3; then 满足所有前提及结论。 我到底错在哪里？

另：用此方法得出结论5个选项全部支持结论。

hazardous

A错误：c=5;l=4;s=2;k=3
其他四个选项在任何情况下都满足，这种题目就用不等式直接看，很简单；不要想去用数字代换，数字取得不好虽然不会立即错掉，但是需要不停地换数字

zjhzkingsam

做逻辑最忌讳的就是你自己臆想一个假设。这里你假设了S>L。这个是题目没有给出的。是你自己想的。其实还存在其他的情况，就是楼上举得。所以这个条件不充分。

xyxxyxxyx

我也得出楼主这个结论。是否哪里错了？
请指教～