Twenty one cylindrical pillars of the Parliament House are to be cleaned. If the diameter of each pillar is 0.50 m and height is 4 m, what will be the cost of cleaning them at the rate of Rs. 2.50 per square matre?

Given,


Number of pillars = 20


Diameter of pillar = 0.50 m


Radius of pillar =


Height of pillar = 4 m


So,


Curved surface area of pillar =


Curved surface area of 20 pillars = 20 ×


Cost of cleaning them at rate Rs.2.50 per m2 = Rs.


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