Q6 of 20 Page 225

A cylindrical piller has a diameter of 56 cm and is of 35 m high. There are 16 pillars around the building. Find the cost of painting the curved surface area of all the pillars at the rate of 5.50 per 1 m2.

Given, A cylindrical pillar, diameter = 56cm = 0.56m i.e. r = 0.28cm

Height h = 35m


Number of pillars n = 16


Curved surface area of a pillar = 2πrh


= 2 × 3.14 × 0.28 × 35


= 61.54cmCurved surface area of 16 pillars = 16 × 61.54


= 984.64cm2


Cost of painting = 5.5 × 984.64


= 5415.52


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