18/12 CR Challenger

The city's center for disease control reports that the rabies epidemic is more serious now than it was two years ago: two years ago less than 25 percent of the local raccoon population was infected, whereas today the infection has spread to more than 50 percent of the raccoon population. However, the newspaper reports that whereas two years ago 32 cases of rabid raccoons were confirmed during a 12-month period in the past 12 months only 18 cases of rabid raccoons were confirmed.


Which one of the following if true, most helps to resolve the apparent discrepancy between the two reports?

(A) The number of cases of rabies in wild animals other than raccoons has increased in the past 12 months.
(B) A significant proportion of the raccoon population succumbed to rabies in the year before last.
(C) The symptoms of distemper another disease to which raccoons are susceptible are usually identical to those of rabies.
(D) Since the outbreak of the epidemic, raccoons, which are normally nocturnal have increasingly been seen during daylight hours
(E) The number of confirmed cases of rabid raccoons in neighboring cities has also decreased over the past year.
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9/12 CR Challenger

In the year following an eight-cent increase in the federal tax on a pack of cigarettes, sales of cigarettes fell ten percent. In contrast, in the year prior to the tax increase, sales had fallen one percent. The volume of cigarette sales is therefore strongly related to the after-tax price of a pack of cigarettes.

The argument above requires which of the following assumptions?

A. During the year following the tax increase, the pretax price of a pack of cigarettes did not increase by as much as it had during the year prior to the tax increase.

B. The one percent fall in cigarette sales in the year prior to the tax increase was due to a smaller tax increase.

C The pretax price of a pack of cigarettes gradually decreased throughout the year before and after the tax increase

D. For the year following the tax increase, the pretax price of a pack of cigarettes was not eight or more cents lower than it had been in the previous year.
E. As the after-tax price of a pack of cigarettes rises, the pretax price also rises

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26/11 CR Challenger

Which of the following most logically completes the argument given?


People in isolated rain-forest communities tend to live on a largely vegetarian diet, and
they eat little salt. Few of them suffer from high blood pressure, and their blood pressure
does not tend to increase with age, as is common in industrialized countries. Such people
often do develop high blood pressure when they move to cities and adopt high-salt diets.
Though suggestive, these facts do not establish salt as the culprit in high blood pressure,
however, because ________.
A. genetic factors could account for the lack of increase of blood pressure with age
among such people.
B. people eating high-salt diets and living from birth in cities in industrialized
societies generally have a tendency to have high blood pressure.
C. it is possible to have a low-salt diet while living in a city in an industrialized
country .
D. there are changes in other aspects of diet when such people move to the city.
E. salt is a necessity for human life, and death can occur when the body loses too
much salt .

Answer and explanation in comments,

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20/11 CR Challenger

Guidebook writer: I have visited hotels throughout the country and have noticed that in those built before 1930 the quality of the original carpentry work is generally superior to that in hotels built afterward. Clearly carpenters working on hotels before 1930 typically worked with more skill, care, and effort than carpenters who have worked on hotels built subsequently.
Which of the following, if true, most seriously weakens the guidebook writer’s argument?
A. The quality of original carpentry in hotels is generally far superior to the quality of original carpentry in other structures, such as houses and stores.
B. Hotels built since 1930 can generally accommodate more guests than those built before 1930.
C. The materials available to carpenters working before 1930 were not significantly different in quality from the materials available to carpenters working after 1930.
D. The better the quality of original carpentry in a building, the less likely that building is to fall into disuse and be demolished.
E. The average length of apprenticeship for carpenters has declined significantly since 1930

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18/11 CR Challenger

18/11 CR Challenger

Environmentalist:

The use of snowmobiles in the vast park north of Milville creates unacceptable levels of air pollution and should be banned.


Milville business spokesperson:

Snowmobiling brings many out-of-towners to Milville in winter months, to the great financial benefit of many local residents. So, economics dictate that we put up with the pollution.

Environmentalist:I disagree: A great many cross-country skiers are now kept from visiting Milville by the noise and pollution that snowmobiles generate.

Environmentalist responds to the business spokesperson by doing which of the following?

A. Challenging an assumption that certain desirable outcome can derive from only one set of circumstances

B. Challenging an assumption that certain desirable outcome is outweighed by negative aspects associated with producing that outcome

C. Maintaining that the benefit that the spokesperson desires could be achieved in greater degree by a different means

D. Claiming that the spokesperson is deliberately misrepresenting the environmentalist

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10/11 CR Challenger

Every fall Croton's jays migrate south. The jays always join flocks of migrating crookbeaks with which they share the summer and winter territories. If a jay becomes separated from the crookbeaks it is accompanying, it wanders until it comes across another flock of crookbeaks. Clearly, therefore, Croton's jays lack the navigational ability to find their way south on their own.

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

A - Croton's jays lay their eggs in the nest of crookbeaks, which breed upon completing their southern migration.
B - The three species of most closely related to crookbeaks do not migrate at all.
C - In the spring, Croton's jays migrate north in the company of Tattersall warblers.
D - Species other than Croton's jays occasionally accompany flocks of migrating crookbeaks.
E - In the spring, crookbeaks migrate north before Croton's jays do.



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CR Challenger 09/11

CR Challenger 09/11
If the ad agency that created the television ad for Tough-As-Nails Tools had thoroughly researched customer demographics, then they would have realized that the majority of frequent tool users are men. Yet the ad was shown during a cooking program targeted to women. However, if the advertisers had not researched customer demographics, then the ad would not have incorporated images depicting the use of tools in home improvement projects as an activity that men enjoy. Yet the ad did so. Therefore the ad agency made some sort of mistake: either the agency did not understand the demographics of the cooking program’s audience or the ad was intended to be shown during a different program.

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


A. The purchasers of products given as gifts are not the ultimate users of those products.

B. Many women, including those who watch cooking programs, occasionally use tools for home improvement projects.

C. The ad agency had never previously aired an ad during a program other than the one intended.

D. Some men, including some who use tools frequently, occasionally watch cooking programs.

E. The ad agency has a reputation for conducting high quality demographic research.




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27/10 CR challengers

Two experimental garden plots were each planted with the same number of tomato plants. Magnesium salts were added to the first plot but not to the second. The first plot produced 20 pounds of tomatoes and the second plot produced 10 pounds. Since nothing else but water was added to either plot, the higher yields in the first plot must have been due to the magnesium salts.

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

(A) A small amount of the magnesium salts from the first plot leached into the second plot.
(B) Tomato plants in a third experimental plot, to which a high-nitrogen fertilizer was added, but no magnesium salts, produced 15 pounds of tomatoes.
(C) Four different types of tomatoes were grown in equal proportions in each of the plots.
(D) Some weeds that compete with tomatoes cannot tolerate high amounts of magnesium salts in the soil.
(E) The two experimental plots differed from each other with respect to soil texture and exposure to sunlight.

answer and explanantion at comments

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13/10 Challenger CR

The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So only if the temperature in the Brazilian ash's environment never exceeds 95 degrees Fahrenheit will its rings be a reliable measure of the tree's age.Which of the following is an assumption on which the argument above depends?

A. The growth of new rings in a tree is not a function of levels of precipitation.

B. Only the Brazilian ash loses rings because of excessive heat.

C. Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.

D. The internal rings of all trees are of uniform thickness.

E. The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

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20-09 CR Challenger

The unemployment rate in the United States fellfrom 7.5 percent in 1981 to 6.9 percent in 1986. Itcannot, however, be properly concluded from thesestatistics that the number of unemployed in 1986was lower than it had been in 1981 because-----.

(A) help-wanted advertisements increased between1981 and 1986

(B) many of the high-paying industrial jobs avail-able in 1981 were replaced by low
-wage ser-vice jobs in 1986, resulting in displacementsof hundreds of thousands of workers
(C) in some midwestern industrial states, the unem-ployment rate was much higher in 1986 thanit had been in 1981
(D) the total available work force, including thosewith and without employment, increasedbetween 1981 and 1986
(E) the average time that employees stay in anyone job dropped during the period 1981to 1986

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CR Challenger 03/09

The purpose of the proposed law requiring a doctor's prescription for obtaining hypodermic needles is to lower the incidence of drug-related deaths, both accidental and intentional, involving hypodermic needles. But even knitting needles can be lethal if they fall into the wrong hands; yet everyone would agree that imposing legal restrictions on obtaining knitting needles would be preposterous. Hence the proposed law involving hypodermic makes no sense and should not be enacted.Which of the following, it true, would provide most support for the argument above?


(A) Knitting needles have been known to cause injury and death.


(B) The benefits of hypodermic needles outweigh those of knitting needles.


(C) The proposed law would not deter the sort of activity known to result in drug-related deaths.


(D) The proposed law could not be effectively enforced.


(E) Knitting needles are not readily available to anybody who wants to obtain them

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28/08 CR

The United Nations General Assembly term runs from September to January. The greatest part of this time is taken up with useless chatter. Delegates debate endlessly, never arriving at decisions. The delegate from each and every 300-square-mile archipelago in the South Pacific must make a lengthy presentation on every topic that reaches the floor, yet almost no attention is paid to solving practical problems that are actually capable of being solved.

The author's argument is based on which one of the following assumptions?

a.The purpose of the General Assembly is to deal with specific practical problems.

b.Too many small states with insignificant problems are members of the General Assembly.

c.If the General Assembly spent less time debating, it would devote most of its attention to providing relief for famine areas.

d.The term of the General Assembly is too short for any important work to be accomplished

e.Members of the General Assembly who are from large countries tend to concentrate more on global issues, rather than on minor topics

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GMAT CR Challenger 16/08

The number of young adults that are illiterate has dropped significantly in a certain county over the last fifteen years. Education officials attribute this decrease entirely to improved conditions in the schools, which made for a better teaching environment, reducing the level of illiteracy.Which of the following, if true, would most seriously weaken the education officials’ explanation for the lower incidence of the disease?
A) Many similar improvements in school conditions have been made over the last twenty-five years in the county.
B) Home-schooling has not been more prevalent among the illiterate as compared to people who are not illiterate.
C) Because of a new assessment scale, many people who until this year would have been considered illiterate are now considered low-level readers.
D) The same percentage of the population has been tested every year for the last 30 years.
E) The conditions in the schools were brought up to the standards of the neighboring counties twenty years ago

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CR in Official Guide 12 Review

Critical Reasoning
In the Critical Reasoning section, nearly 1/3 of the published questions fit into "Advanced Applications" as introduced in the Veritas Prep "Critical Reasoning 2" lesson. These categories (e.g. "Assumption" or "Useful to Evaluate") feature convoluted question stems and require specific strategies to successfully solve the most difficult problems. In many cases, these questions closely parallel the advanced Logical Reasoning questions featured on the Law School Admission Test (LSAT), thus students can make good use of the logic training in the Veritas Prep "Arguments" lesson and subsequent Critical Reasoning lessons. For several years, Veritas Prep has hypothesized that, in order to make the GMAT verbal section more challenging, GMAC would adopt more advanced Critical Reasoning questions like those found on the LSAT. The new questions featured in the 12th edition support that hypothesis, and demonstrate the value of the increasing emphasis that we place on these advanced topics in our prep materials.

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01/08 CR Challenger

Bank deposits are credited on the date of the transaction only when they are made before 3.pm. Alicia knows that the bank deposit was made before 3 p.m . So, Alicia knows that the bank deposit was credited on the date of the transaction.

Which one of the following exhibits both of the logical flaws exhibited by the argument above?

(A) Journalists are the only ones who will be permitted to ask questions at the press conference. Since Marjorie is a journalist, she will be permitted to ask questions.

(B) We know that Patrice works only on Thursday. Today is Thursday, so it follows that Patrice is working today.

(C) It is clear that George knows he will be promoted to shift supervisor, because George will be promoted to shift supervisor only if Helen resigns, and George knows Helen will resign.

(D) John believes that 4 is a prime number and that 4 is divisible by 2. Hence John believes that there is a prime number divisible by 2.

(E) Pat wants to become a social worker. It is well known that social workers are poorly paid. Pat apparently wants to be poorly paid

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30/07 CR

In the course of her researches, a historian recently found two documents mentioning the same person, Erich Schnitzler. One, dated May 3, 1739, is a record of Schnitzler’s arrest for peddling without a license. The second, undated, is a statement by Schnitzler asserting that he has been peddling off and on for 20 years.

The facts above best support which of the following conclusions?

(A) Schnitzler started peddling around 1719.
(B) Schnitzler was arrested repeatedly for peddling.
(C) The undated document was written before 1765.
(D) The arrest record was written after the undated document.
(E) The arrest record provides better evidence that Schnitzler peddled than does the undated document.

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23/07 CR

Frobisher, a sixteenth-century English explorer, had soil samples from Canada's Kodlunarn Island examined for gold content. Because high gold content was reported, Elizabeth I funded two mining expeditions. Neither expedition found any gold there. Modern analysis of the island's soil indicates a very low gold content. Thus the methods used to determine the gold content of Frobisher's samples must have been inaccurate.

Which of the following is an assumption on which the argument depends?

(A) The gold content of the soil on Kodlunarn Island is much lower today than it was in the sixteenth century.

(B) The two mining expeditions funded by Elizabeth I did not mine the same part of Kodlunarn Island.

(C) The methods used to assess gold content of the soil samples provided by Frobisher were different from those generally used in the sixteenth century.

(D) Frobisher did not have soil samples from any other Canadian island examined for gold content.

(E) Gold was not added to the soil samples collected by Frobisher before the samples were examined.

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