Flawed Parallel ReasoningDiff: Hard
Logic Breakdown
Passage Summary: The argument claims that because a majority of mechanics are experienced, and a majority of experienced mechanics know circuits, then a majority of all mechanics must know circuits.
Conclusion: Most auto mechanics understand electronic circuits.
Reasoning: Most auto mechanics have extensive experience, and most mechanics with that experience understand electronic circuits.
Analysis: This is a classic 'Most + Most' flaw. In logic, just because 51% of A are B, and 51% of B are C, it does not mean that any A are C, let alone a majority of them. The 51% of B that are C could be the 49% of B that are not A at all. To find the parallel flaw, look for an answer that attempts to chain two 'most' statements together to reach a 'most' conclusion. It’s like saying most people in this room are tall, and most tall people like basketball; that doesn't guarantee that most people in this room like basketball.
Conclusion: Most auto mechanics understand electronic circuits.
Reasoning: Most auto mechanics have extensive experience, and most mechanics with that experience understand electronic circuits.
Analysis: This is a classic 'Most + Most' flaw. In logic, just because 51% of A are B, and 51% of B are C, it does not mean that any A are C, let alone a majority of them. The 51% of B that are C could be the 49% of B that are not A at all. To find the parallel flaw, look for an answer that attempts to chain two 'most' statements together to reach a 'most' conclusion. It’s like saying most people in this room are tall, and most tall people like basketball; that doesn't guarantee that most people in this room like basketball.
Passage Stimulus
Passage Redacted
Unlock Full Passage23.The pattern of flawed reasoning in which one of the following arguments is most similar to that in the argument above?
Correct Answer
E
E matches the flawed pattern exactly: Most snow-removal companies (A) run lawn-care services (B). Most companies that run lawn-care services (B) hire additional workers (C). Therefore, most snow-removal companies (A) hire additional workers (C). This mirrors the invalid ‘most + most -> most’ inference.
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