Flawed ReasoningDiff: Easy
Logic Breakdown
Passage Summary: Jim used a magnet to see if a substance had iron in it. Because the substance stuck to the magnet, he decided it must be iron.
Conclusion: The substance Jim tested definitely contains iron.
Reasoning: Magnets are known to attract iron, and since the substance was attracted to the magnet, it must be iron.
Analysis: Jim is a bit overeager with his magnet and his logic. He assumes that because iron is magnetic, anything magnetic must be iron, which is a classic formal logic error known as affirming the consequent. To find the flaw, look for an answer that suggests other substances might also be attracted to magnets, which would ruin Jim's 'iron-only' theory.
Conclusion: The substance Jim tested definitely contains iron.
Reasoning: Magnets are known to attract iron, and since the substance was attracted to the magnet, it must be iron.
Analysis: Jim is a bit overeager with his magnet and his logic. He assumes that because iron is magnetic, anything magnetic must be iron, which is a classic formal logic error known as affirming the consequent. To find the flaw, look for an answer that suggests other substances might also be attracted to magnets, which would ruin Jim's 'iron-only' theory.
Passage Stimulus
Passage Redacted
Unlock Full Passage1.Jim's reasoning is questionable in that it fails to consider the possibility that
Correct Answer
D
Magnets attract substances other than iron (e.g., nickel, cobalt, certain steels), so the substance’s attachment does not prove it contains iron. This is the overlooked alternative that makes Jim’s reasoning questionable.
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