10. Some people say that the scarcity of food is a function of the finite limits of the earth’s resources, coupled with a relentless rate of population growth. This analysis fails to recognize, however, that much of the world’s agricultural resources are used to feed livestock instead of people. In the United States, for example, almost one-half of the agricultural acreage is devoted to crops fed to livestock. A steer reduces twenty-one pounds of inexpensive grain to one pound of expensive meat. Thus, the scarcity of food is not merely a function of limited resources and population growth.
Which one of the following is an assumption that would allow the conclusion in the argument to be properly drawn?
(A) People prefer eating meat to eating grain.
(B) Meat is twenty-one times more expensive than grain.
(C) The limits of the earth’s agricultural resources are not finite.
(D) More than one-half of the agricultural acreage in the United States is devoted to crops fed to humans.
(E) Growing crops for human consumption of the acreage currently devoted to crops for livestock will yield more food for more people.
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本题的关键点是：土地的有限性 与 人口增长之间的关系。
作者的论据：有相当一部分土地被用来种植饲料类作物。
作者的结论：人口增长不会导致粮食的缺乏。
他的前提是：若这部分土地用来种植人类消费的粮食，可以保证增长人口的需要。
A：有部分weaken的作用。因为由于人们偏肉食，则随人口的增长，最肉类的需求会不断增高。由之导致耕种饲料的土地总面积也会增加（由于题目没提到生产技术的问题，所以不用考虑技术的提高，也可提到农业产出），这些土地面积的增加，必定导致生产人类消费的粮食的土地面积的减少。这就会导致粮慌。
B：无关选项。题目中有关这样的信息一点也没有。
最多能考虑成weaken选项，因为肉贵会促使人们种牲口粮食，导致人类消费粮食土地面积的减少，从而导致粮慌。当然，这个推想只是推想。实际上是属于超题目信息的考虑方式。这是GMAT逻辑思维的大忌！
C：直接与原文的信息相反。
D：也是与原文的信息相反。原文是几乎，而D中是肯定。
E：正确选项。
就是我前面写的前提。
9. Free public education is the best form of education there is. Therefore, we must fight to ensure its continued existence; that is, we must be ready to defend the principle of equality of educational opportunity. Because this principle is well worth defending, it is clear that free public education is better than any other form of education.
Which one of the following illustrates the same weak reasoning as found in the passage?
(A) I love music, and that’s why I listen to it constantly. I have my stereo or radio on every waking minute. Since I play music all the time, I must really love it.
(B) Books are my most valuable possessions. My books are like my friends—each pleases me in different ways. Just as I would give up everything to save my friends, so too with my books.
(C) I would much rather be poor and respected than be rich and despised. To have the respect of others is far more valuable than to have millions of dollars.
(D) I have never been betrayed by any of my friends. They have been true to me through good times and bad. Therefore I will never betray any of my friends.
(E) Because every plant I have ever seen has green leaves, I have concluded that all plants must have green leaves. This looks like a plant but it does not have green leaves, so it cannot be a plant.
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这一题是lsat中常见的逻辑相似题，这种题型比较简单，只要弄清楚原文的论证过程即可，无需对结论，前提产生过多联想。
原文中的论证顺序就是因为A，所以B；又因为B，所以A。（循环论证）
符合这种双重因果论证的只有a.
b,d一层因果关系，c,无因果，e,因为A，所以B；又因为非B，所以非A
Conclusion: Thus, the (scarcity) of food is not merely a function of limited resources and population growth.
Premise: that much of the world’s agricultural resources are used to feed livestock instead of people. ( eg: In U.S, 1/2 the agricultural acreage -> Livestock. A steer consume 21 pounds gain, produing 1 pound meat)
Asking: Assumption to make the conclusion reasonable.
D.Growing crops for human consumption of the acreage (currently devoted to crops for livestock)will yield more food for more people. Saying: Growing corps devoted to livestock is a reason for the scarcity of food, that is , other two reasons mentioned are not the whole .
Is it complicated, isn't ? How to quickly fix the question?
Actually, check the premise ( mention a new reason) and conclusion( the two reasons is incompleted) ,you want to make the conclusion reasonable and then you need a assumption that :the new reason is a reason for the phenomenon.
Actually, checking the premise ( mention a new reason) and conclusion( the two reasons is incompleted),you will get a hint for a assumption to make the conclusion reasonable that :the new reason is a reason for the phenomenon.
11. Hanifah: A recent survey shows that there are fewer people who drive only on weekends than there are people who drive to work each weekday. As a result, weekend-only drives are involved in fewer accidents. Therefore, insurance rates should be adjusted so that rates would be significantly higher for the regular commuters.
Katsu: I can’t agree with your conclusion. The same study also showed that, although weekend-only drives are involved in fewer accidents, when considered on the basis of accidents-per-mile-driven their records are worse than those of regular commuters. Therefore, insurance rates should be adjusted to increase the rates of weekend-only drivers over those of regular commuters.
In the conversation above, Katus does which one of the following?
(A) Katsu disagrees with each of the premises of the argument that Hanifah offers.
(B) Katsu cites additional evidence stating that weekend-only drivers are actually involved in a greater number of accidents than regular commuters.
(C) Katsu accuses Hanifah of using inaccurate statistical information.
(D) Kasu proves that Hanifah didn’t read the entire report that was cited.
(E) Katsu disagrees with Hanifah over how accident records are to be evaluated for insurance rates.
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读完题目的感觉：两人用了不同的论据支持各自的结论。其中K 在开始还承让了一下。
A：错误选项。因为两人的前提是一样的：事故发生率高，则应承担较高的保险费。
B：前半段是可取的。虽然是在同一个调查中，但K用的是另外的evidence。
后半段是错误的。因为K已经承认weekend-only drives are involved in fewer accidents
C：错误选项。因为K在开始的阶段，即承让部分，是同意H的部分说法的。
D：最无聊的选项。不知道怎么评价这个选项。
E：正确选项。因为两人用来确定保险的指标是不一样的。
