In 90 percent of the commercial airline accidents last year, one or another of a group consisting of only 18...
GMAT Critical Reasoning : (CR) Questions
In 90 percent of the commercial airline accidents last year, one or another of a group consisting of only 18 percent of the world's commercial airlines was involved. Since the other 82 percent of airlines were generally flying the same types of airplanes as the accident-prone airlines, significant differences in safety procedures must have been responsible for these differences in safety records.
Which of the following, if true about the world's commercial airlines last year, most seriously weakens the argument above?
Passage Analysis:
| Text from Passage | Analysis |
| In 90 percent of the commercial airline accidents last year, one or another of a group consisting of only 18 percent of the world's commercial airlines was involved. |
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| Since the other 82 percent of airlines were generally flying the same types of airplanes as the accident-prone airlines, significant differences in safety procedures must have been responsible for these differences in safety records. |
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Argument Flow:
The argument starts with striking statistics showing that a small percentage of airlines account for most accidents. It then eliminates one possible explanation (airplane types) to conclude that safety procedures must be the cause.
Main Conclusion:
Significant differences in safety procedures must have been responsible for the differences in safety records between the accident-prone airlines and the safer ones.
Logical Structure:
This uses elimination reasoning: Since we know the accident patterns are different AND we know the airplane types are similar, the author concludes that safety procedures must be the differentiating factor. The logic assumes these are the only two possible explanations.
Prethinking:
Question type:
Weaken - We need to find information that would reduce our belief in the conclusion that safety procedures are responsible for the accident differences
Precision of Claims
The argument makes specific numerical claims (90% of accidents, 18% of airlines) and a causal claim about safety procedures being the key difference, while ruling out airplane types as a factor
Strategy
To weaken this argument, we need to find alternative explanations for why 18% of airlines had 90% of accidents that don't involve safety procedures. The author assumes safety procedures are the cause after ruling out airplane types, so we should look for other factors the author didn't consider - like flight volume, route difficulty, or operational differences
This choice provides a powerful alternative explanation for the accident pattern. It shows that 15% of airlines were responsible for 97% of all air miles flown and were involved in 87% of accidents. This suggests that exposure (flight volume) rather than safety procedures could explain why certain airlines have more accidents. Airlines that fly significantly more miles naturally have more opportunities for accidents to occur. This directly weakens the argument by offering a compelling alternative to the safety procedures explanation.
This choice actually strengthens rather than weakens the argument. If the accident-prone airlines were cited for more safety violations, this supports the author's conclusion that safety procedures (or lack thereof) are responsible for the accident differences. We're looking for information that weakens the safety procedures explanation, not supports it.
This choice describes what happens after accidents occur (customer switches, flight cancellations) but doesn't explain why the accidents happened in the first place. Since we need to weaken the explanation for the original accident pattern, information about post-accident consequences is irrelevant to the argument.
This choice about 20% of airlines employing military personnel doesn't clearly relate to either safety procedures or accident rates. It provides no clear logical connection to explain why certain airlines would have more accidents, so it neither strengthens nor weakens the argument effectively.
This choice about 24% of airplanes being over fifteen years old doesn't help because the author already established that both groups of airlines fly "the same types of airplanes." Even if age were a factor, this choice doesn't tell us whether the older planes are concentrated among the accident-prone airlines or distributed evenly, making it irrelevant to the argument.