11. Exercise Problems VIII

A bus stop is barricaded from the remaining part of the road, by using $50$ hollow cones made of recycled cardboard. Each cone has a base diameter of $40 cm$ and height $1 m$. If the outer side of each of the cones is to be painted and the cost of painting is $Rs.12$ per $m^2$ , what will be the cost of painting all these cones? (Use $π = 3.14$ and take $\sqrt{1.04} = 1.02$)

 

Cost of painting: