gmat逻辑题削弱题例题二
6. (Z4-21)An overwhelming proportion of the most productive employees at SaleCo’s regional offices work not eight hours a day, five days a week, as do other SaleCo employees, but rather ten hours a day, four days a week, with Friday off. Noting this phenomenon, SaleCo’s president plans to increase overall productivity by keeping the offices closed on Fridays and having all employees work the same schedule—ten hours a day, four days a week.
Which of the following, if true, provides the most reason to doubt that the president’s plan, if implemented, will achieve its stated purpose?
A. Typically, a SaleCo employee’s least productive hours in the workplace are the early afternoon hours.
B. None of the employees who work four days a week had volunteered to work that schedule, but all were assigned to it by their supervisors.
C. Working ten hours a day has allowed the most productive employees to work two hours alone each day in their respective offices relatively undisturbed by fellow employees.
D. Employees at SaleCo are compensated not on the basis of how many hours a week they work but on the basis of how productive they are during the hours they are at work.
E. Those SaleCo employees who have a four-day workweek do not take any of their office work to do at home on Fridays.
7.(Z3-15) Lightbox, Inc., owns almost all of the movie theaters in Washington County and has announced plans to double the number of movie screens it has in the county within five years. Yet attendance at Lightbox’s theaters is only just large enough for profitability now and the county’s population is not expected to increase over the next ten years. Clearly, therefore, if there is indeed no increase in population, Lightbox’s new screens are unlikely to prove profitable.
Which of the following, if true about Washington County, most seriously weakens the argument?
A. Though little change in the size of the population is expected, a pronounced shift toward a younger, more affluent, and more entertainment-oriented
population is expected to occur.
B. The sales of snacks and drinks in its movie theaters account for more of Lightbox’s profits than ticket sales do.
C. In selecting the mix of movies shown at its theaters, Lightbox’s policy is to avoid those that appeal to only a small segment of the moviegoing population.
D. Spending on video purchases, as well as spending on video rentals, is currently no longer increasing.
E. There are no population centers in the county that are not already served by at least one of the movie theaters that Lightbox owns and operates.
8.(Z3-28)Wind farms, which generate electricity using arrays of thousands of wind-powered turbines, require vast expanses of open land. County X and County Y have similar terrain, but the population density of County X is significantly higher than that of County Y. Therefore, a wind farm proposed for one of the two counties should be built in County Y rather than in County X.
Which of the following, if true, most seriously weakens the planner’s argument?
A. County X and County Y are adjacent to each other, and both are located in the windiest area of the state.
B. The total population of County Y is substantially greater than that of County X.
C. Some of the electricity generated by wind farms in County Y would be purchased by users outside the county.
D. Wind farms require more land per unit of electricity generated than does any other type of electrical-generation facility.
E. Nearly all of County X’s population is concentrated in a small part of the county, while County Y’s population is spread evenly throughout the country.
9. (Z5)Of patients over 65 years old who survived coronary bypass surgery—a procedure widely prescribed for people with heart disease—only 75 percent benefited from the surgery. Thus it appears that for one in four such patients, the doctors who advised them to undergo this surgery, with its attendant risks and expense, were more interested in an opportunity to practice their skills and in their fee than in helping the patient.
Which of the following, if true, most seriously undermines the argument?
A. Many of the patients who receive coronary bypass surgery are less than 55 years old.
B. Possible benefits of coronary bypass surgery include both relief from troubling symptoms and prolongation of life.
C. Most of the patients in the survey decided to undergo coronary bypass surgery because they were advised that the surgery would reduce their risk of future heart attacks.
D. The patients over 65 years old who did not benefit from the coronary bypass surgery were as fully informed as those who did benefit from the surgery as to the risks of the surgery prior to undergoing it.
E. The patients who underwent coronary bypass surgery but who did not benefit from it were medically indistinguishable, prior to their surgery, from the patients who did benefit.
10.(Z5-30)Printwell’s Ink Jet Division manufactures ink-jet printers and the ink cartridges they use. Sales of its ink-jet printers have increased. Monthly revenues from those sales, however, have not increased, because competition has forced Printwell to cut the prices of its printers. Unfortunately, Printwell has been unable to bring down the cost of manufacturing a printer. Thus, despite the increase in printer sales, the Ink Jet Division must be providing the company with much smaller than it used to.
Which of the following, if true, most seriously weakens the argument?
A. Ink-jet printers in regular use frequently need new ink cartridges, and Printwell’s printers only accept Printwell’s ink cartridges.
B. Unlike some competing companies, Printwell sells all of its printers through retailers, and these retailers’ costs account for a sizable proportion of the printers’ ultimate retail price.
C. Some printer manufacturers have been forced to reduce the sale price of their ink-jet printers even more than Printwell has.
D. In the past year, no competing manufacturer of ink-jet printers has had as great an increase in unit sales of printers as Printwell has.
E. In the past year, sales of Printwell’s ink-jet printers have increased more than sales of any other type of printer made by Printwell.