WeakenDiff: Hard
Logic Breakdown
Passage Summary: An expert claims that a drop of a specific person's blood makes a small stain because ten test drops all resulted in small stains.
Conclusion: A single drop of the defendant's blood creates a stain significantly smaller than 9.5 square centimeters on that specific fabric.
Reasoning: In ten controlled tests, a single drop of the defendant's blood consistently produced a stain between 4.5 and 4.8 square centimeters, which is much less than the expected 9.5 square centimeters.
Analysis: To weaken this argument, we need to find a reason why those ten test drops might not represent how the blood usually behaves. The expert assumes the 'controlled circumstances' of the test accurately reflect the conditions relevant to the 9.5 cm² expectation. Look for an answer that suggests the test drops were smaller than a 'standard' drop or that the fabric used in the test was treated differently than the fabric in the comparison case. If the drops used in the experiment weren't actually 'full' drops, the whole conclusion about the blood's staining properties collapses.
Conclusion: A single drop of the defendant's blood creates a stain significantly smaller than 9.5 square centimeters on that specific fabric.
Reasoning: In ten controlled tests, a single drop of the defendant's blood consistently produced a stain between 4.5 and 4.8 square centimeters, which is much less than the expected 9.5 square centimeters.
Analysis: To weaken this argument, we need to find a reason why those ten test drops might not represent how the blood usually behaves. The expert assumes the 'controlled circumstances' of the test accurately reflect the conditions relevant to the 9.5 cm² expectation. Look for an answer that suggests the test drops were smaller than a 'standard' drop or that the fabric used in the test was treated differently than the fabric in the comparison case. If the drops used in the experiment weren't actually 'full' drops, the whole conclusion about the blood's staining properties collapses.
Passage Stimulus
Passage Redacted
Unlock Full Passage17.Which one of the following, if true, most undermines the value of the evidence for the expert witness's conclusion?
Correct Answer
C
C introduces an eleventh test that yields 9.3 cm²—still below 9.5, but not “much less.” This outlier breaks the tight 4.5–4.8 pattern and shows the results can vary substantially, undermining the probative force of the 10 tests for the “much less” claim.
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