Difficulty: Easy
Correct Answer: 56m
Explanation:
Introduction / Context:
This classic geometry problem links area of a circle to its radius, modeling the rope length as the radius of the grazing circle.
Given Data / Assumptions:
Concept / Approach:
Area A = πr^2 → r = sqrt(A/π). The rope length equals r.
Step-by-Step Solution:
Verification / Alternative check:
Area with r = 56: πr^2 = (22/7)*56*56 = (22/7)*3136 = 22*448 = 9856. Perfect match.
Why Other Options Are Wrong:
16m, 14m, 76m, 64m do not square to 3136 when used with π = 22/7 to produce 9856 m^2.
Common Pitfalls:
Using diameter instead of radius, or incorrect π handling during division.
Final Answer:
56m
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