GMAT逻辑复习资料-逻辑大全分类-Assumption

大豆

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大全-4-17.        One state adds a 7 percent sales tax to the price of most products purchased within its jurisdiction. This tax, therefore, if viewed as tax on income, has the reverse effect of the federal income tax : the lower the income, the higher the annual percentage rate at which the income is taxed.
结论：收入越低，每年税额所占收入的比例越高。
Federal tax works in a way that the higher the income is, the higher the tax rate is. The sales tax is opposite: the lower the income, the higher the tax rate (because the 7% is on the goods purchased and steady).
题目意思：州税增加了购物税，如果这也算做收入税的一部分，就违反了联邦的收入税方针－－收入少，收入税就应该少．而这样增加购物税的结果就成了收入越少，收入税所占的比例越高。
收入税比率=交税收入/总收入
总收入少，交税收入相同的情况下（即居民花在需要交税的商品上的钱在各收入阶层是相等的，就是说大款和叫花子花同样多的钱买这些商品），收入税比率才会大。
The conclusion above would be properly drawn if which of the following were assumed as a premise?
(A) The amount of money citizens spend on products subject to the state tax tends to be equal across income levels.
(B) The federal income tax favors citizens with high incomes, whereas the state sales tax favors citizens with low incomes.
(C) Citizens with low annual incomes can afford to pay a relatively higher percentage of their incomes in state sales tax, since their federal income tax is relatively low.
(D) The lower a state’s sales tax, the more it will tend to redistribute income from the more affluent citizens to the rest of society.（A）
(E) Citizens who fail to earn federally taxable income are also exempt from the state sales tax.

大豆

大全-18-5.        Under current federal law, employers are allowed to offer their employees free parking spaces as a tax-free benefit, but they can offer employees only up to $180 per year as a tax-free benefit for using mass transit. The government could significantly increase mass transit ridership by raising the limit of this benefit to meet commuters’ transportation costs.
The proposal above to increase mass transit ridership assumes that
(A) current mass transit systems are subject to unexpected route closings and delays
(B) using mass transit creates less air pollution per person than using a private automobile
(C) the parking spaces offered by employers as tax-free benefits can be worth as much as $2,500 per year
(D) many employees are deterred by financial considerations from using mass transit to commute to their places of employment(D)
deter from doing sth: make sb not want to do
很多员工是出于经济上的考虑才不使用公共交通而自己开车上下班的。
(E) because of traffic congestion on major commuter routes, it is often faster to travel to one’s place of employment by means of mass transit than by private automobile

大豆

大全-18-9.        Technically a given category of insurance policy is underpriced if, over time, claims against it plus expenses associated with it exceed total income from premiums. But premium income can be invested and will then yield returns of its own. Therefore, an underpriced policy does not represent a net loss in every case.
The argument above is based on which of the following assumptions?
(A) No insurance policies are deliberately underpriced in order to attract customers to the insurance company offering such policies.
(B) A policy that represents a net loss to the insurance company is not an underpriced policy in every case.
(C) There are policies for which the level of claims per year can be predicted with great accuracy before premiums are set.
(D) The income earned by investing premium income is the most important determinant of an insurance company’s profits.(E)
(E) The claims against at least some underpriced policies do not require paying out all of the premium income from those policies as soon as it is earned.
如果premium income需要马上全部支付出去,那么就不可能有被用来invest的了,也不可能yield returns了.结论就不成立.

大豆

大全-16-2.        The reason much refrigerated food spoils is that it ends up out of sight at the back of the shelf. So why not have round shelves that rotate? Because such rotating shelves would have just the same sort of drawback, since things would fall off the shelves’ edges into the rear corners.
Which of the following is presupposed in the argument against introducing rotating shelves?
(A) Refrigerators would not be made so that their interior space is cylindrical.
如果interior space是cylindrical的，那么就不存在rear corners的问题了。
(B) Refrigerators would not be made to have a window in front for easy viewing of their contents without opening the door.
(C) The problem of spoilage of refrigerated food is not amenable to any solution based on design changes.
(D) Refrigerators are so well designed that there are bound to be drawbacks to any design change.
(E) Rotating shelves would be designed to rotate only while the refrigerator door was open.

大豆

大全-15-3.        Installing scrubbers in smokestacks and switching to cleaner-burning fuel are the two methods available to Northern Power for reducing harmful emissions from its plants. Scrubbers will reduce harmful emissions more than cleaner-burning fuels will. Therefore, by installing scrubbers, Northern Power will be doing the most that can be done to reduce harmful emissions from its plants.
Which of the following is an assumption on which the argument depends?
(A) Switching to cleaner-burning fuel will not be more expensive than installing scrubbers.
(B) Northern Power can choose from among various kinds of scrubbers, some of which are more effective than others.
(C) Northern Power is not necessarily committed to reducing harmful emissions from its plants.
(D) Harmful emissions from Northern Power’s plants cannot be reduced more by using both methods together than by the installation of scrubbers alone.
(E) Aside from harmful emissions from the smokestacks of its plants, the activities of Northern Power do not cause significant air pollution.

大豆

大全-15-10.        If the county continues to collect residential trash at current levels, landfills will soon be overflowing and parkland will need to be used in order to create more space. Charging each household a fee for each pound of trash it puts out for collection will induce residents to reduce the amount of trash they create; this charge will therefore protect the remaining county parkland.
Which of the following is an assumption made in drawing the conclusion above?
(A) Residents will reduce the amount of trash they put out for collection by reducing the number of products they buy.
(B) The collection fee will not significantly affect the purchasing power of most residents, even if their households do not reduce the amount of trash they put out.
(C) The collection fee will not induce residents to dump their trash in the parklands illegally.
(D) The beauty of county parkland is an important issue for most of the county’s residents.
(E) Landfills outside the county’s borders could be used as dumping sites for the county’s trash.

大豆

大全-15-14.        Although computers can enhance people’s ability to communicate, computer games are a cause of underdeveloped communication skills in children. After-school hours spent playing computer games are hours not spent talking with people. Therefore, children who spend all their spare time playing these games have less experience in interpersonal communication than other children have.
The argument depends on which of the following assumptions?
(A) Passive activities such as watching television and listening to music do not hinder the development of communication skills in children.
(B) Most children have other opportunities, in addition to after-school hours, in which they can choose whether to play computer games or to interact with other people.
(C) Children [who do not spend all of their after-school hours playing computer games] spend at least some of that time talking with other people.
(D) Formal instruction contributes little or nothing to children’s acquisition of communication skills.
(E) The mental skills developed through playing computer games do not contribute significantly to children’s intellectual development.

大豆

大全-15-16.        Commentator: The theory of trade retaliation states that countries closed out of any of another country’s markets should close some of their own markets to the other country in order to pressure the other country to reopen its markets. If every country acted according to this theory, no country would trade with any other.
The commentator’s argument relies on which of the following assumptions?
(A) No country actually acts according to the theory of trade retaliation.
(B) No country should block any of its markets to foreign trade.
(C) Trade disputes should be settled by international tribunal.
(D) For any two countries, at least one has some market closed to the other.
(E) Countries close their markets to foreigners to protect domestic producers.

大豆

大全-13-3.        Within 20 years it will probably be possible to identify the genetic susceptibility an individual may have toward any particular disease. Eventually, effective strategies will be discovered to counteract each such susceptibility. Once these effective strategies are found, therefore, the people who follow them will never get sick.
The argument above is based on which of the following assumptions?
(A) For every disease there is only one strategy that can prevent its occurrence.
(B) In the future, genetics will be the only medical specialty of any importance.
(C) All human sicknesses are in part the result of individuals’ genetic susceptibilities.
(D) All humans are genetically susceptible to some diseases.
(E) People will follow medical advice when they are convinced that it is effective.

大豆

大全-12-9.        In 1990 all of the people who applied for a job at Evco also applied for a job at Radeco, and Evco and Radeco each offered jobs to half of these applicants. Therefore, every one of these applicants must have been offered a job in 1990.
The argument above is based on which of the following assumptions about these job applicants?
(A) All of the applicants were very well qualified for a job at either Evco or Radeco.
(B) All of the applicants accepted a job at either Evco or Radeco.
(C) None of the applicants was offered a job by both Evco and Radeco.
(D) None of the applicants had applied for jobs at places other than Evco and Radeco.
(E) None of the applicants had previously worked for either Evco or Radeco.