Flawed ReasoningDiff: Hardest
Logic Breakdown
Passage Summary: A therapist claims that 50 weeks of therapy is enough for most people because 75% of the types of problems studied were fixed in that timeframe.
Conclusion: Fifty weekly therapy sessions are sufficient for the majority of people.
Reasoning: A study of sixty different psychological problems found that approximately 75 percent of those specific problems were resolved within fifty weeks of therapy.
Analysis: The argument commits a serious 'units' error by conflating the percentage of *problems* with the percentage of *people*. Even if 75% of the *types* of problems are solved quickly, it's possible that the remaining 25% of problems are the ones that affect 90% of the actual population. If most people suffer from the 'difficult' problems, then 50 sessions would not be enough for 'most people.' Look for an answer that identifies this failure to consider how the problems are distributed across the population of patients.
Conclusion: Fifty weekly therapy sessions are sufficient for the majority of people.
Reasoning: A study of sixty different psychological problems found that approximately 75 percent of those specific problems were resolved within fifty weeks of therapy.
Analysis: The argument commits a serious 'units' error by conflating the percentage of *problems* with the percentage of *people*. Even if 75% of the *types* of problems are solved quickly, it's possible that the remaining 25% of problems are the ones that affect 90% of the actual population. If most people suffer from the 'difficult' problems, then 50 sessions would not be enough for 'most people.' Look for an answer that identifies this failure to consider how the problems are distributed across the population of patients.
Passage Stimulus
Passage Redacted
Unlock Full Passage25.The therapist's argument is logically most vulnerable to criticism on the grounds that it
Correct Answer
B
B highlights the critical gap: even if 75% of the studied problem types clear within 50 weeks, it may still be that one (or more) of the slow-to-clear problems afflicts most people. If a slow problem is widespread, then most people would need more than 50 sessions, undercutting the therapist’s conclusion.
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