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:
r^2 = A / π = 9856 / (22/7) = 9856 * 7 / 229856 / 22 = 448 → r^2 = 448 * 7 = 3136r = sqrt(3136) = 56 mVerification / 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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