Flawed ReasoningDiff: Medium
Logic Breakdown
Passage Summary: A salesperson 'proves' their vacuum is better by showing it can pick up leftover dirt after a different vacuum already went over the spot once.
Conclusion: The Super XL is a superior vacuum cleaner compared to the customer's current model.
Reasoning: The Super XL was able to extract dirt from a carpet that the customer's old vacuum had already passed over once.
Analysis: The salesperson's 'test' is hilariously unfair because it lacks a control group. By running the Super XL second, they are essentially showing that two passes over a carpet pick up more than one pass—which would likely be true even if you used the old vacuum twice! Look for an answer that identifies this failure to account for the order of the trial or the cumulative nature of cleaning.
Conclusion: The Super XL is a superior vacuum cleaner compared to the customer's current model.
Reasoning: The Super XL was able to extract dirt from a carpet that the customer's old vacuum had already passed over once.
Analysis: The salesperson's 'test' is hilariously unfair because it lacks a control group. By running the Super XL second, they are essentially showing that two passes over a carpet pick up more than one pass—which would likely be true even if you used the old vacuum twice! Look for an answer that identifies this failure to account for the order of the trial or the cumulative nature of cleaning.
Passage Stimulus
Passage Redacted
Unlock Full Passage10.The vacuum cleaner salesperson's argument is most vulnerable to the criticism that it
Correct Answer
E
It identifies the order effect: had the Super XL been used first, the old vacuum might also have picked up leftover dirt. The salesperson’s test fails to control for order, so it doesn’t establish superiority.
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