GMAT Critical reasoning 오답노트 (4) weakening

1. In the United States, certain states use the death penalty to punish those who commit murder. Other states do not use the death penalty in such cases, but rather sentence murderers to life in prison. (evidence)In the states that do use the death penalty, the murder rate per 100,000 persons is higher than the rate in the states that do not use the death penalty. (conclusion)Thus the death penalty only causes more murders and should be repealed in all states to reduce the murder rate.

Assumption: The rate of murder in the states that use the death penalty increased.

Which of the following, if true, would most weaken the argument above?

		Each state that has enacted the death penalty in murder cases over the last twenty years has seen a decline in the murder rate since the passage of those laws.
		Many consider the death penalty to be morally wrong in all cases and oppose it regardless of the potential deterrent to murder.
		In states that use the death penalty, some murderers are still only sentenced to life in prison.
		The annual rate of non-violent crime is lower in states with the death penalty than it is in states without the death penalty.
		In each state that uses the death penalty, over 60 percent of the state's citizens support the death penalty and believe that it is an effective deterrent to murder.

This argument is basically saying that the death penalty causes increased murders. In order to weaken this argument you must show that (1) 증거반박 the death penalty does not cause more murders or (2) that something else is responsible for the increased murder rate in states that have the death penalty. Choice (A) does this best. It tells us that the murder rate actually declined in states after they adopted the death penalty. If this is true, it does not follow that the death penalty causes increased murders. (*증거의 내용을 바꾸지 않고, 결론을 바꿀 수 있어야 한다)

The opinions of people about the death penalty do not affect the quality of this argument, thus choices (B) and (E) are not correct.

Even if the death penalty is not applied in all murder cases – as stated in choice (C) – it does not follow that the death penalty is actually causing more murders.

Choice (D) might actually strengthen the argument. If non-violent crime is lower in states with the death penalty, but murders are higher, then it might be that the death penalty does cause additional murders if the presence of the death penalty is the only difference between the two states. We are looking to weaken this argument, so choice (D) is incorrect.

2. Wunderlitch park, located in Madison county, has a strict regulation requiring mountain bicyclists to wear helmets. Recently, a group of bicyclists acknowledged that helmets may prevent injuries to the wearer, but protested claiming (evidence)the park should only regulate activities that may hurt a third party. Hence, the bicyclists argued that (conclusion)they should have the right to refrain from wearing helmets.

Assumption: the wearing helmet has nothing to do with hurting a third party. 

Which of the following, if true, most seriously weakens the conclusion in the passage?

		Ninety percent of bicyclists who use Wunderlitch park prefer to wear a helmet to protect themselves in case of an accident.
		Lawyers for Wunderlitch park have warned that the repeal of the helmet regulation would lead to an increase in general admission park entrance fees to cover the legal expenses associated with personal injury lawsuits.
		Motorcyclists in a neighboring county are required to wear a helmet while on the road.
		Parks that require the use of helmets have a lower percentage of accidents resulting in deaths than parks that don't require the use of helmets.
		More bicyclists who do not wear helmets are seriously injured in accidents than bicyclists who do wear helmets.

The bicyclists conclude they shouldn't be forced to wear helmets. In supporting their argument, the bicyclists claim parks should only regulate activities that may endanger others. The argument assumes that riding without a helmet would not hurt others. Choice (B) weakens the argument's conclusion by invalidating this assumption. Specifically, choice (B) shows that the repeal of the regulation would cause an increase in park entrance fees.

Choice (A) is outside the scope of the argument because it fails to address the validity of the regulation.

Choice (C) is outside the scope of the argument because regulations on motorcyclists in a neighboring county do not affect bicycle regulations in Wunderlitch park.

Choices (D) and (E) provide evidence that wearing a helmet prevents injury to the bicyclist. These choices, however, do not weaken the bicyclist's argument because the protesting bicyclists acknowledge the benefits of helmets to the wearer.

3. (conclusion)The candy manufacturer's claim that employee "theft" costs the company thousands of dollars a year in potential sales is greatly overstated. (evidence) Most of the candy eaten on the job and not paid for is eaten one piece at a time, by workers who would not be willing to buy an entire box of it anyway.

Assumption: the amount of candy eaten one piece at a time by employee is a small fraction of the candy that has little impact on the potential sales. 

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

		The workers eat only defective candies that could not be sold.
		Candy eaten by employees represents lost potential sales to non-employees.
		A few workers account for most of the candy that is eaten but not paid for.
		Most of the candies eaten by employees are consumed during the holiday season, when production outputs are at their highest.
		The amount of candy eaten by employees is only a small fraction of the candy sold by the company.

THE CONCLUSION: Candy manufacturers don't really lose thousands every year in potential sales through workers eating candy.

THE EVIDENCE: workers eat the candy one piece at a time and wouldn't buy a whole box anyway.

The argument as stated assumes that the candy would, if not eaten, only be sold to the people who are eating it — the workers. We can undermine this assumption by pointing out that the candy could easily be sold to other people.

If the workers only eat candy that couldn't be sold (A), then the manufacturers probably aren't losing potential sales. This is an au contraire choice. It doesn't matter how many workers are eating the candy (C); what's important is how much is disappearing and whether it could be sold if it weren't being eaten. The issue of when the candy is eaten (D) is irrelevant to whether the company is losing potential sales. Even if the eaten candy is a small fraction of the candy sold (E), it could still represent a substantial loss of potential sales money.

4. One Zydol capsule contains (evidence)twice the pain reliever found in regular aspirin. A consumer will have to take two aspirin in order to get the relief provided by one Zydol. And since a bottle of Zydol (evidence)costs the same as a bottle of regular aspirin, consumers can be expected to switch to Zydol.

Assumption: Customers would consider its price the most unless the effects of the medicine are different. 

Which of the following, if true, would most weaken the argument that consumers will be discontinuing the use of regular aspirin and switching to Zydol?

		A regular bottle of aspirin contains more than twice as many capsules as does a bottle of Zydol.
		The pain reliever in Zydol is essentially the same pain reliever found in regular aspirin.
		Some headache sufferers experience a brief period of dizziness shortly after taking Zydol but not after taking regular aspirin.
		Neither regular aspirin nor Zydol is as effective in the relief of serious pain as are drugs available only by prescription.
		A Zydol capsule is twice as large as the average aspirin.

THE CONCLUSION: Consumers can be expected to switch to Zydol.

THE EVIDENCE: Although one has to take two aspirins to get the relief provided by one Zydol, nevertheless a bottle of Zydol costs the same as a bottle of aspirin. The implication is that Zydol is more cost-effective than aspirin: you get a much better bargain with a bottle of Zydol. But if the aspirin bottle contains more than twice as many tablets as the Zydol bottle, then it's the aspirin bottle that gives you more pain reliever for your money.

The argument concerns which is the better bargain, not which is the better pain reliever. Thus it doesn't matter (B) that the ingredient is the same. (C) points to some consumers who won't want Zydol. Perhaps, but one, these may be very few, and two, this doesn't attack the author's reasoning, which is based on cost. Pain sufferers who don't have a doctor's prescription are left with the same choice between Zydol and aspirin, so (D) doesn't weaken Zydol's case against aspirin. Even if you make an unwarranted leap and assume that there may be fewer of the large Zydol pills (E) per bottle, choice (A) clearly does a better job of arguing along this line.

5. A manufacturer of large truck engines recently developed a new engine with increased horse power than the earlier engine put out by the company. During the last year, when both engines were sold, the earlier engine outsold the new model by a factor of two to one. The management of the truck engine manufacturer concluded that the company's customers do not care about increased horse power(마력).

Which of the following, if true, would most seriously weaken the conclusion reached by the management of the truck engine manufacturer?

		Many types of customers buy this company's truck engines, including private truck enthusiasts and commercial truck companies.
		A number of horse power increasing accessories for the earlier engine sold well during the last year and these products are not yet available for the new engine.
		Many customers of this truck engine manufacturer also purchase truck engines from companies that did not come out with a new, higher horse power, engine in the last year.
		The newer engine can be used in all the same trucks as the earlier engine.
		There was not a significant difference in price between the new engine and the earlier version of the engine put out by this manufacturer.

The management of the truck engine manufacturer has concluded that their customers do not value additional horse power based on the fact that the company's new, higher horse power, engine was outsold by a previous version of the same engine. Your task is to weaken this argument, so you must find the answer choice that suggests some other reason (other than customers not caring about additional power) for the difference in sales. Choice (B) does this nicely by suggesting that customers may be buying the lower horse power engine, but then also purchasing horse power enhancing accessories for their engines.

Choices (A) and (C) are ultimately irrelevant for this argument. If customers are diverse or they buy from other manufacturers, it does not weaken the possibility that they do not, as a group, care about horse power.

Choices (D) and (E) both strengthen the argument by removing other possibilities for why the earlier engine outsold the newer engine. It could have been that the new engine was unpopular because it could not be used for the same applications as the earlier engine. It could also have been true that the new engine was prohibitively expensive. Both would have been reasons why customers would have favored the earlier engine despite lower horse power, but both are removed if these answer choices were true.