Difficulty: Easy
Correct Answer: 32.25%
Explanation:
Introduction / Context:With height fixed, a cone’s volume is proportional to r^2. A percentage increase in radius thus compounds as the square of the radius factor for the volume.
Given Data / Assumptions:
Concept / Approach:Compute the volume scale factor as (1.15)^2. Convert that factor into a percentage increase by subtracting 1 and multiplying by 100%.
Step-by-Step Solution:New factor = (1.15)^2 = 1.3225Percent increase = (1.3225 − 1)*100% = 32.25%
Verification / Alternative check:For small p, the approximation would be ≈ 2p = 30%, but the exact square gives 32.25%, slightly higher.
Why Other Options Are Wrong:30% is a linear approximation; 31% and 34.75% are off the exact square; 32.25% matches the precise compounding.
Common Pitfalls:Applying the linear percentage directly to volume rather than squaring the radius factor.
Final Answer:32.25%
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