GMAT - Graduate Management Admission Verbal: Critical Reasoning Assumptions Questions and Answers 1 — Questions and Answers
Question 1: A city implemented a mandatory helmet law for all cyclists. A year later, the number of serious head injuries from cycling accidents reported by local hospitals had decreased by 20%. The city council therefore concluded that the helmet law was successful in reducing serious head injuries among cyclists. The city council's conclusion depends on which of the following assumptions?
- The number of cyclists and the overall frequency of cycling accidents did not significantly decrease in the year after the law was implemented. (Correct answer)
- All cyclists in the city complied with the new mandatory helmet law.
- The 20% decrease in reported injuries is the most significant public health improvement the city has seen in the last year.
- Local hospitals did not change their criteria for what constitutes a 'serious head injury' during the period in question.
Correct answer: The number of cyclists and the overall frequency of cycling accidents did not significantly decrease in the year after the law was implemented.
The argument concludes that the helmet law caused the reduction in reported injuries. For this to be true, other potential causes for the reduction must be ruled out. If the number of cyclists or the number of accidents decreased for other reasons (e.g., bad weather, new bike lane construction causing detours), that could also explain the drop in injuries. The argument assumes this was not the case. Let's use the Negation Test: If the number of cyclists and accidents *did* significantly decrease, then the drop in injuries could be due to less cycling, not the helmet law. This would weaken the conclusion. Therefore, the original statement is a necessary assumption.
Question 2: The CEO of InnovateCorp announced that the company will cut its research and development (R&D) budget by 30% to improve short-term profitability. The stated goal of this move is to make the company's stock more attractive to investors in the next fiscal quarter. The argument that this plan will achieve its goal rests on which of the following assumptions?
- InnovateCorp's competitors will not increase their R&D spending in response.
- The quality of InnovateCorp's research will not decline despite the budget cuts.
- The investors InnovateCorp aims to attract prioritize immediate profitability over the potential for long-term growth. (Correct answer)
- The 30% budget cut will be sufficient to make InnovateCorp profitable in the next quarter.
Correct answer: The investors InnovateCorp aims to attract prioritize immediate profitability over the potential for long-term growth.
The argument links cutting R&D (a driver of future growth) to attracting investors. This logic only works if the target investors value the immediate financial benefit (higher short-term profit) more than they value the thing being sacrificed (long-term innovation and growth potential). The argument assumes this specific investor preference. If we negate this assumption (i.e., if investors prioritize long-term growth over short-term profit), the CEO's plan would actually make the stock *less* attractive, thus destroying the argument's conclusion.
Question 3: A study found that people who regularly own pets have, on average, lower blood pressure than people who do not. The study's authors concluded that acquiring a pet is an effective therapeutic strategy for lowering one's blood pressure. Which of the following is an assumption on which this conclusion depends?
- The benefits of pet ownership on blood pressure are not limited to a specific type of pet, such as dogs or cats.
- People with naturally low blood pressure are not inherently more likely to own pets than people with high blood pressure. (Correct answer)
- The study's participants were representative of the general population in terms of age and health.
- Owning a pet is more effective at lowering blood pressure than traditional medical interventions.
Correct answer: People with naturally low blood pressure are not inherently more likely to own pets than people with high blood pressure.
The argument moves from a correlation (pet ownership and lower blood pressure) to a causal conclusion (getting a pet *causes* lower blood pressure). This assumes there isn't a reverse causality or a third factor causing both. The correct answer addresses the possibility of reverse causality. If people who already have low blood pressure are, for some reason, more likely to get pets in the first place, then the observed correlation wouldn't mean that pets lower blood pressure. The argument must assume this is not the case. Negating the assumption—that people with low blood pressure *are* more likely to get pets—would severely weaken the conclusion that getting a pet is a therapeutic strategy.
Question 4: Archaeologists excavating a site found written tablets detailing grain transactions that were all dated within a single 10-year period. No tablets from before or after this period were found at the site. The lead archaeologist concluded that the settlement was actively used for trade for only that specific 10-year period. The archaeologist's conclusion is properly drawn only if which of the following is assumed?
- The tablets found constitute the complete record of all grain transactions that occurred during the 10-year period.
- The inhabitants of the settlement did not use a different, less durable medium for record-keeping in other periods. (Correct answer)
- The settlement was not inhabited for purposes other than trade during any other period.
- The grain mentioned in the tablets was the primary agricultural product of the settlement.
Correct answer: The inhabitants of the settlement did not use a different, less durable medium for record-keeping in other periods.
The conclusion is that trade only occurred for 10 years, based on the evidence of tablets from only that period. The argument assumes that the evidence found (or lack thereof) is representative of the activity that took place. If the inhabitants used a different record-keeping method in other periods (like papyrus, which decays) that did not survive, then trade could have occurred for much longer. The conclusion relies on the assumption that if trade had happened at other times, similar, durable evidence would have been left behind and found. Negating this—that they *did* use a less durable medium—breaks the link between the evidence and the conclusion.
Question 5: To reduce traffic congestion, the city of Oakhaven plans to implement a 'congestion pricing' system, charging drivers a fee to enter the downtown area during peak hours. The city planner predicts that this policy will significantly reduce the number of cars downtown and encourage the use of public transportation. Which of the following is an assumption underlying the city planner's prediction?
- The revenue generated from the congestion fee will be sufficient to fund improvements to public transportation.
- A significant number of drivers who currently travel downtown have access to viable public transportation alternatives. (Correct answer)
- The congestion fee will be set at a price point that is higher than the average cost of a public transit fare.
- Neighboring cities have not implemented similar congestion pricing plans.
Correct answer: A significant number of drivers who currently travel downtown have access to viable public transportation alternatives.
The plan's success hinges on drivers changing their behavior—specifically, switching to public transit. For this switch to happen, public transportation must be a realistic option for them. If there are no viable public transit routes for the majority of drivers, they may have no choice but to pay the fee and continue driving, thus defeating the plan's purpose. The planner must assume that such alternatives exist. If we negate this (i.e., viable alternatives are *not* available), the prediction that people will switch to public transit and reduce traffic falls apart.
Question 6: A pharmaceutical company found that a new drug, MedX, was effective in 80% of patients in a clinical trial. The company's marketing materials claim that anyone suffering from the target disease has an 80% chance of being helped by MedX. This marketing claim is based on which of the following questionable assumptions?
- The patients in the clinical trial are representative of the entire population of individuals with the disease. (Correct answer)
- The 20% of patients for whom the drug was not effective experienced no harmful side effects.
- MedX is more effective than any other drug currently on the market for the disease.
- The positive effects of MedX are permanent for the 80% of patients it helps.
Correct answer: The patients in the clinical trial are representative of the entire population of individuals with the disease.
The argument generalizes a result from a specific sample (the clinical trial participants) to a much broader population (all individuals with the disease). This leap of logic is only valid if the sample group is truly representative of the general patient population in all relevant aspects (e.g., age, severity of illness, other health conditions). If the trial participants were, for example, all younger and healthier than the typical patient, the drug's effectiveness in the real world might be much lower. The claim assumes the trial group is a perfect mirror of the total patient population. Negating this—that the trial group is *not* representative—undermines the claim that any given person has an 80% chance of success.
GMAT - Graduate Management Admission Verbal: Critical Reasoning Assumptions Questions and Answers 1
A city implemented a mandatory helmet law for all cyclists.
A year later, the number of serious head injuries from cycling accidents reported by local hospitals had decreased by 20%.
The city council therefore concluded that the helmet law was successful in reducing serious head injuries among cyclists.
The city council's conclusion depends on which of the following assumptions?