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    Question

    A hemispherical bowl made of iron has an inner diameter

    of 84 cm. Find the cost of tin plating it on the inside at the rate of Rs.21 per 100cm² take π=22/7
    A 2348.48 Correct Answer Incorrect Answer
    B 2328.48 Correct Answer Incorrect Answer
    C 2248.96 Correct Answer Incorrect Answer
    D 1114.24 Correct Answer Incorrect Answer

    Solution

    Diameter = 84cm then r =42cm The total surface area of the hemispherical bowl = 4πr²/ 2 =πr² =2× (22/7) ×42×42 =2×22×42×6 =11088cm² Cost of tin plating = 100cm² = 21Rs 1cm² = .21 Rs then 11088cm² = .21 × 11088cm² =2328.48 Rs

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