Necessary AssumptionDiff: Medium
Logic Breakdown
Passage Summary: You have to work out both sides of your back evenly so that the muscles pull on your spine with equal strength, keeping everything straight.
Conclusion: Maintaining a healthy back requires exercising the muscles on both sides of the spine to the same degree.
Reasoning: Balanced muscle development is essential for spinal health because muscles must pull with equal force from opposite sides to keep the spine aligned.
Analysis: The author assumes a direct link between the 'amount of exercise' and the 'amount of pull.' However, what if someone's back is already lopsided? In that case, equal exercise might just maintain the imbalance. The argument requires the assumption that equal exercise is the way to achieve that necessary equal pull. When looking for the necessary assumption, ask yourself: 'If this weren't true, would the recommendation to exercise equally still guarantee a healthy back?'
Conclusion: Maintaining a healthy back requires exercising the muscles on both sides of the spine to the same degree.
Reasoning: Balanced muscle development is essential for spinal health because muscles must pull with equal force from opposite sides to keep the spine aligned.
Analysis: The author assumes a direct link between the 'amount of exercise' and the 'amount of pull.' However, what if someone's back is already lopsided? In that case, equal exercise might just maintain the imbalance. The argument requires the assumption that equal exercise is the way to achieve that necessary equal pull. When looking for the necessary assumption, ask yourself: 'If this weren't true, would the recommendation to exercise equally still guarantee a healthy back?'
Passage Stimulus
Passage Redacted
Unlock Full Passage17.Which one of the following is an assumption required by the argument?
Correct Answer
B
B links the recommendation (exercise equally) to the stated need (balanced development) by noting that unequal exercise tends to cause unbalanced development. Negation test: if unequal exercise did not tend to cause imbalance, exercising equally would not be important for maintaining a healthy back, which collapses the argument.
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