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Probability

Question

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A hemispherical bowl made of brass has inner diameter 10.5 cm. Find the cost of tin-plating it on the inside at the rate of ` 16 per 100 cm2.

Solution

Inner diameter = 10.5 cm

therefore

Inner radius (r) =

fraction numerator 10.5 over denominator 2 end fraction space cm space equals space 5.25 space cm

Inner surface area = 2πr²

equals 2 cross times 22 over 7 cross times left parenthesis 5.25 right parenthesis squared equals 173.25 space cm squared

Cost of tin-plating at the rate of र 16 per 100 cm^{2
$equals straight र space 16 over 100 cross times 173.25 equals straight र space 27.72$}

Some More Questions From Probability Chapter

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