A hemispherical bowl made of brass has inner diameter 10.5 cm. Find the cost of the plating it on the inside at the rate of Rs. 4 per 100 cm2.
Surface area of a hemisphere = 2πr2
Given, diameter of the hemisphere bowl is 10.5 cm
Surface area of the bowl = 2 × (22/7) × (10.5/2)2 = 173.25 cm2
Given, cost of the plating it on the inside at the rate of Rs. 4 per 100 cm2
Cost of plating the hemisphere bowl 
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