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A tent is of the shape of a right circular cylinder up to a height of $3$ metres surmounted by a right circular cone of same radius such that the total height of the tent is $13.5$ metres above the ground. Calculate the cost of painting the inner side of the tent at the rate of ₹ $2$ per square metre, if the radius of the base is $14$ metres.
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$l = \sqrt{14^2 + (10.5)^2} = 17.5$ m. Total Surface Area (inside) = $2 \times \frac{22}{7} \times 14 \times 3 + \frac{22}{7} \times 14 \times 17.5 = 1034$ m$^2$. Cost = $1034 \times 2 = \text{\text{Rs} } 2068$