Length of rope from grazing area of a cow A cow grazes a circular region of area 2826 m². Find the required rope length (radius) in metres (use π ≈ 3.14).
Aptitude
Area
Difficulty: Easy
Choose an option
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A15 m
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B30 m
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C24 m
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D36 m
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ENone of these
Answer
Correct Answer: 30 m
Explanation
Introduction / Context:Converting a given circular area to radius is a standard application of A = πr^2, widely used in practical geometry and land measurement problems.
Given Data / Assumptions:
- Area A = 2826 m^2
- π ≈ 3.14
Concept / Approach:Radius r = sqrt(A/π). The rope length equals this radius.
Step-by-Step Solution:
r^2 = 2826 / 3.14 = 900 r = sqrt(900) = 30 mVerification / Alternative check:Check area with r = 30: A = 3.14 * 900 = 2826 m^2, matching perfectly.
Why Other Options Are Wrong:15 m, 24 m, and 36 m would yield areas not equal to 2826 m^2 with π = 3.14.
Common Pitfalls:Using circumference formula instead of area or mishandling the square root step are frequent mistakes.
Final Answer:30 m