Question

    The circumference of a circle is equal to the perimeter

    of a rectangle whose length and breadth are in ratio 13:10, respectively. If the area of the rectangle is 25480 cm2, then find the radius of the circle.
    A 102.45cm Correct Answer Incorrect Answer
    B 95cm Correct Answer Incorrect Answer
    C 101.6cm Correct Answer Incorrect Answer
    D 86cm Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Let the length and breadth of the rectangle be 10x cm and 10x cm, respectively According to the question, 13x × 10x = 25480  x2 = 25480/130 = 196  x = 14 Therefore, perimeter of the rectangle = 2 × (13x + 10x) = 644cm Let the radius of the circle be ‘r’ cm. According to the question, 2πr = 644 Or r = 644× (7/44) = 102.45cm

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