Flawed ReasoningDiff: Easy
Logic Breakdown
Passage Summary: A resident claims that because 30% of local homes have one problem and 30% have another, a total of 60% of the town's housing stock must be flawed.
Conclusion: At least 60 percent of the houses in the town have either drainage problems or structural defects.
Reasoning: Thirty percent of the houses have poor site drainage and another thirty percent have structural defects.
Analysis: The resident is falling into a classic statistical trap: the assumption of exclusivity. They are simply adding the two percentages together, which only works if no house belongs to both groups. If there is any overlap—meaning some houses have both bad drainage and structural defects—the total percentage of unique houses with problems would be lower than 60%. I'll bet you've seen this in real life; a house with a leaky foundation (drainage) is often the same one with a sagging roof (structural). Look for an answer that identifies this failure to account for overlap.
Conclusion: At least 60 percent of the houses in the town have either drainage problems or structural defects.
Reasoning: Thirty percent of the houses have poor site drainage and another thirty percent have structural defects.
Analysis: The resident is falling into a classic statistical trap: the assumption of exclusivity. They are simply adding the two percentages together, which only works if no house belongs to both groups. If there is any overlap—meaning some houses have both bad drainage and structural defects—the total percentage of unique houses with problems would be lower than 60%. I'll bet you've seen this in real life; a house with a leaky foundation (drainage) is often the same one with a sagging roof (structural). Look for an answer that identifies this failure to account for overlap.
Passage Stimulus
Passage Redacted
Unlock Full Passage5.The reasoning in the resident's argument is flawed in that the argument overlooks the possibility that
Correct Answer
E
E identifies the overlooked overlap: some houses with structural defects also have inadequate drainage. That double-counting would make the true combined percentage less than 60%, undermining the “at least 60%” claim.
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