Difficulty: Medium
Correct Answer: 8 : 5
Explanation:
Introduction / Context:Curved (lateral) surface area of a cylinder depends on radius and height; for a cone it depends on radius and slant height. With the same radius and height, we compute each and then form the ratio.
Given Data / Assumptions:
Concept / Approach:Compute l, then both CSAs, then the ratio.
Step-by-Step Solution:
l = √(6^2 + 8^2) = √(36 + 64) = √100 = 10CSA_cylinder = 2π * 6 * 8 = 96πCSA_cone = π * 6 * 10 = 60πRatio = 96π : 60π = 8 : 5Verification / Alternative check:Cancel π to simplify; ratio reduces cleanly to 8:5.
Why Other Options Are Wrong:Other ratios do not match the computed CSA values with l = 10.
Common Pitfalls:Using height instead of slant height in the cone’s CSA; forgetting to compute l by Pythagoras.
Final Answer:8 : 5
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