Weaken an Argument
Help Questions
GRE Verbal › Weaken an Argument
A public health department concludes that a new advertising campaign caused a recent increase in flu vaccinations. The department notes that in the month after the campaign began, the number of vaccinations administered at local clinics rose by 15% compared with the previous month. The department therefore plans to run the same campaign every year to raise vaccination rates. Which of the following, if true, most weakens the argument?
The campaign’s advertisements were placed primarily on social media platforms used heavily by younger adults.
The department’s overall budget for health education is higher this year than it was five years ago.
In the same month the campaign began, several large employers in the area began requiring proof of flu vaccination for on-site work.
Some clinics reported that they temporarily ran out of a particular brand of flu vaccine.
The campaign did not include advertisements in languages other than English.
Explanation
This question tests your ability to weaken an argument attributing increased flu vaccinations to an advertising campaign. To weaken this causal claim, you need to identify another factor that could explain the 15% increase. The health department assumes their campaign caused the increase and plans to repeat it annually based on this assumption. The Borrect answer (B) provides a powerful alternative explanation: several large employers began requiring proof of flu vaccination for on-site work in the same month. This mandate would naturally drive vaccination rates up regardless of any advertising campaign, seriously undermining the conclusion that the campaign deserves credit. Choice A about social media placement describes the campaign's method but doesn't weaken the causal claim, while choice C about temporary vaccine shortages might actually suggest the campaign was too successful rather than weakening it.
A museum director argues that extending the museum’s hours to include Friday evenings will increase annual attendance. The director cites a three-month trial in which Friday-evening attendance averaged 400 visitors per night, and notes that the museum’s daytime attendance did not decline during the trial. The director concludes that making Friday-evening hours permanent will add those visitors to the annual total and will therefore increase ticket revenue. Which of the following, if true, most weakens the argument?
During the trial period, the museum hosted a popular temporary exhibition that ended shortly after the trial concluded.
The museum’s annual membership program includes unlimited daytime admission.
A nearby theater also offers discounted tickets on Friday evenings.
The museum’s café experienced higher sales on Friday evenings during the trial.
Some museum employees prefer working evening shifts to working early-morning shifts.
Explanation
This question tests weakening an argument that permanent Friday evening hours will increase annual museum attendance and revenue. To weaken this conclusion, you need evidence suggesting the trial results won't translate to permanent increases. The director assumes that the 400 visitors per Friday evening represent new, additional attendance that will continue indefinitely. The Aorrect answer (A) reveals that a popular temporary exhibition was running during the trial and ended shortly after, suggesting that the high Friday evening attendance may have been driven by this special exhibition rather than the extended hours themselves. This means making the hours permanent might not sustain those attendance levels once the exhibition is gone. Choice C about café sales actually supports the extended hours, while choice D about nearby theater discounts doesn't explain why the trial attendance wouldn't continue.
A university committee argues that because students in sections of Introductory Statistics that used weekly low-stakes quizzes earned higher final exam scores than students in sections without weekly quizzes, the university should require weekly quizzes in all large introductory courses to improve learning outcomes. The committee’s reasoning assumes that the quizzes themselves caused the score increase and that similar effects will occur across other subjects. Which of the following casts the most doubt on the argument?
In the statistics course, the sections with weekly quizzes were taught by instructors with, on average, more years of teaching experience than instructors of sections without quizzes.
Several departments already use occasional quizzes, though not on a weekly schedule.
The final exam in Introductory Statistics includes questions that closely resemble those on the weekly quizzes.
Some students report that weekly quizzes increase stress, even when each quiz counts for a small portion of the grade.
Students in many large introductory courses attend optional review sessions before major exams.
Explanation
This question tests weakening an argument about educational interventions. To weaken means to provide evidence that the conclusion doesn't necessarily follow from the premises. The committee assumes that weekly quizzes caused the higher exam scores and that this effect will transfer to other subjects. The vulnerability in this reasoning is the assumption that the quizzes themselves, rather than other factors, produced the improvement. Answer A seriously weakens the argument by introducing a confounding variable: instructors with more teaching experience taught the sections with weekly quizzes. This suggests that instructor quality, not the quizzes, may have caused the higher scores, undermining the committee's conclusion about requiring quizzes universally. Answer D, about exam questions resembling quiz questions, actually strengthens rather than weakens the argument by providing a mechanism for how quizzes might improve scores.
A manufacturer proposes replacing its current packaging with a lighter material, noting that a pilot test on one product line reduced shipping costs by 6% over three months. The manufacturer concludes that switching all product lines to the lighter packaging will reduce the company’s total shipping costs by at least 6% annually. The proposal assumes that the pilot test results will generalize across products and time. Which of the following, if true, most weakens the argument?
The lighter packaging costs slightly more per unit than the current packaging.
The lighter packaging is made from a material that some customers perceive as less premium than the current packaging.
During the pilot test, fuel surcharges imposed by the company’s main carrier temporarily decreased, lowering shipping costs for all shipments regardless of packaging.
Some product lines are shipped primarily to international destinations rather than domestic ones.
The pilot product line accounts for a small share of the company’s total annual shipments by weight.
Explanation
This question asks you to weaken an argument about packaging and shipping costs. Weakening involves finding information that challenges the reasoning or introduces factors that undermine the conclusion. The manufacturer assumes that the 6% cost reduction in the pilot test was due to the lighter packaging and will generalize across all products and time periods. The critical assumption is that no other factors influenced shipping costs during the pilot. Answer B most effectively weakens the argument by revealing that fuel surcharges temporarily decreased during the pilot test, lowering all shipping costs regardless of packaging. This means the 6% reduction may have been due to external market conditions rather than the packaging change, seriously undermining the conclusion about future savings. Answer D, about higher packaging costs, addresses total costs but doesn't challenge the specific claim about shipping cost reduction.
A beverage company tested a new label design on its bottled tea in two regions and found that sales in those regions rose by 8% compared with the previous quarter. The company concludes that the new label design increases consumer purchases and decides to roll out the label nationwide. The company notes that the tea’s price and formula were unchanged and that the regions tested are representative of the national market. Which of the following casts the most doubt on the argument?
The company’s bottled tea is sold in more flavors nationwide than in the two test regions.
In the test regions, the company also secured additional shelf space at several large retailers during the same quarter.
Sales of bottled water in the test regions fell slightly during the same quarter.
Some consumers report that they prefer label designs that use fewer colors than the new design.
The new label design costs slightly more per bottle to print than the old label design.
Explanation
This question tests weakening an argument about a new label design causing increased tea sales. To weaken this argument effectively, you must identify information that suggests another factor could explain the 8% sales increase. The company assumes the label design alone drove sales, controlling for price and formula. The Aorrect answer (A) reveals that the company also secured additional shelf space at large retailers in the test regions during the same period. More shelf space typically leads to increased visibility and sales, providing an alternative explanation for the sales boost that has nothing to do with the label design. This seriously undermines the conclusion about rolling out the label nationwide. Choice D about higher printing costs addresses profitability rather than causation, while choice E about bottled water sales is irrelevant to whether the tea label caused increased tea sales.
A city’s transportation office reports that after installing adaptive traffic-signal software on three major corridors last year, average commute times on those corridors fell by 12%. The office concludes that expanding the same software to all intersections citywide will reduce overall city commute times by a similar amount. The office notes that the three corridors were selected because they are among the busiest in the city and argues that improvements there indicate the software’s effectiveness in general. Which of the following, if true, most weakens the argument?
During the year the software was installed, a major employer on one of the three corridors shifted 30% of its workforce to remote work, reducing peak-hour traffic volume on that corridor.
The adaptive software requires annual licensing fees that are higher than the fees for the city’s current signal-timing system.
In a nearby city, a different brand of adaptive traffic-signal software produced mixed results when first introduced.
Several neighborhoods not located near the three corridors have recently requested additional pedestrian crossings at intersections.
On a few minor streets that intersect the three corridors, drivers reported slightly longer waits at red lights after the software was installed.
Explanation
This question tests your ability to weaken an argument about the effectiveness of adaptive traffic-signal software. Weakening an argument means finding information that reduces support for the conclusion that expanding the software citywide will reduce overall commute times. The argument assumes that the 12% improvement on three corridors occurred because of the software itself, not due to other factors. The Borrect answer (B) undermines this assumption by revealing that a major employer shifted 30% of its workforce to remote work on one corridor, which would naturally reduce traffic and commute times regardless of the software. This alternative explanation for the improvement suggests the software may not be as effective as claimed. Choice A about pedestrian crossings is irrelevant to the software's effectiveness on traffic flow, while choice C about licensing fees doesn't address whether the software actually works.
A coastal town proposes building a seawall to prevent future flood damage. Town officials argue that because a smaller seawall built near the harbor five years ago has not been overtopped during storms since its construction, a larger seawall along the entire coastline will protect residential areas as well. They conclude that investing in the seawall is the most effective way to reduce flood-related repair costs over the next decade. Which of the following, if true, most weakens the argument?
The proposed seawall would require periodic maintenance to address corrosion from saltwater exposure.
Property values in the town have increased over the past five years.
During the past decade, the town has spent more on road repairs than on flood repairs.
Some residents prefer nature-based solutions, such as restoring dunes, to large infrastructure projects.
The harbor area where the existing seawall was built is sheltered by offshore rock formations, while much of the town’s coastline is fully exposed to open-ocean waves.
Explanation
This question asks you to weaken an argument that a larger seawall will protect the entire coastline based on a smaller harbor seawall's success. Weakening requires showing why the harbor's success might not translate to the broader coastline. The officials assume that because the harbor seawall hasn't been overtopped in five years, a similar structure will work equally well everywhere along the coast. The Borrect answer (B) reveals a crucial difference: the harbor is sheltered by offshore rock formations while much of the coastline faces open-ocean waves. This means the harbor seawall faced much less severe conditions than a coastal seawall would face, making the comparison invalid and seriously undermining the conclusion. Choice A about resident preferences doesn't address effectiveness, while choice C about maintenance needs doesn't challenge whether the seawall would actually prevent flooding.
A hospital introduced a new scheduling system intended to reduce patient wait times in its outpatient clinic. After implementation, the average reported wait time fell from 46 minutes to 34 minutes. The hospital administrator concludes that the scheduling system is responsible and recommends adopting it in all hospital departments that schedule appointments. The administrator adds that the clinic’s staffing levels remained constant, so the scheduling change must explain the improvement. Which of the following, if true, most weakens the argument?
Some patients in the outpatient clinic prefer to arrive early even when appointments are scheduled later in the day.
During the same period, the clinic reduced the number of appointment slots per day by lengthening the standard appointment duration.
Several departments in the hospital use different electronic medical record systems than the outpatient clinic uses.
The outpatient clinic began sending automated reminder messages that reduced last-minute cancellations.
The new scheduling system requires staff training that takes several hours to complete.
Explanation
This question asks you to weaken an argument attributing reduced wait times to a new scheduling system. Weakening requires finding evidence that something other than the scheduling system could explain the improvement from 46 to 34 minutes. The administrator assumes that because staffing remained constant, the scheduling system must be responsible for the change. The Correct answer (C) provides a compelling alternative explanation: the clinic reduced the number of appointment slots by lengthening appointments, which would naturally reduce congestion and wait times regardless of the scheduling system. This directly undermines the conclusion that the scheduling system deserves credit and should be adopted elsewhere. Choice B about reminder messages might help with efficiency but doesn't directly explain shorter wait times, while choice E about training requirements doesn't address whether the system actually works.
A regional electric utility claims that offering customers a rebate for installing smart thermostats will reduce peak electricity demand enough to avoid building a new substation. The utility bases this conclusion on a small pilot program in which participating households used 10% less electricity during peak hours than they had the previous summer. The utility argues that because peak demand is driven largely by residential air-conditioning use, expanding the rebate program will produce similar reductions at scale. Which of the following, if true, most weakens the argument?
The rebate amount is larger than rebates offered by neighboring utilities for similar devices.
Some households in the pilot program reported that they liked being able to control their thermostat from a phone app.
The utility’s customer satisfaction ratings improved slightly after the pilot program began.
The smart thermostats in the pilot program were manufactured by several different companies.
Commercial buildings account for a substantial portion of the region’s peak electricity demand, and their demand has been rising faster than residential demand.
Explanation
This question asks you to weaken an argument about smart thermostats reducing peak electricity demand enough to avoid building a new substation. Weakening requires showing that the conclusion doesn't follow from the evidence about residential reductions. The utility assumes that because residential air-conditioning drives peak demand, a 10% household reduction will scale up to avoid needing new infrastructure. The Borrect answer (B) undermines this by revealing that commercial buildings account for a substantial portion of peak demand and their demand is rising faster than residential. This means that even if the residential program succeeds, it may not reduce overall peak demand enough to avoid the substation, since commercial demand isn't addressed. Choice A about customer preferences doesn't address whether the program reduces demand sufficiently, while choice C about rebate amounts compared to other utilities is irrelevant to effectiveness.
A school district piloted a new mathematics curriculum in five middle schools and observed that, after one year, the average math test score in those schools increased by 6 percentage points. The superintendent concludes that adopting the curriculum in all district middle schools will raise math scores districtwide. The superintendent notes that the pilot schools include a range of socioeconomic backgrounds and that teachers received the same amount of training as usual. Which of the following statements most seriously undermines the conclusion?
The pilot schools administered a different version of the math test than they had used the previous year, and the new version was designed to be easier for students at that grade level.
The pilot schools replaced several retiring math teachers with newly hired teachers during the pilot year.
Several teachers in nonpilot schools have expressed interest in using supplemental online practice tools.
The new curriculum includes more word problems than the previous curriculum did.
The district’s science test scores remained roughly constant during the same year.
Explanation
This question tests your ability to weaken an argument about a new mathematics curriculum improving test scores. To weaken effectively, you need to identify factors other than the curriculum that could explain the 6-point increase. The superintendent assumes the curriculum caused the improvement and will produce similar results districtwide. The Dorrect answer (D) severely undermines this by revealing that the pilot schools used an easier version of the test, which would naturally produce higher scores regardless of curriculum quality. This alternative explanation suggests the curriculum may not be responsible for the improvement at all. Choice B about new teachers is somewhat relevant but doesn't clearly explain higher scores, while choice C about science scores is irrelevant to whether the math curriculum works.