Q11 of 62 Page 22

Find the cost of plastering the inner surface of a well at Rs. 9.50 per m2, if it is 21 m deep and diamwter of its top is 6 m.

Given,


Height of cylinder = 21 m


Diameter of cylinder = 6 m


Radius of cylinder =


So,


Curved surface area of cylinder =


∴ Cost of plastering the inner surface at rate Rs.9.50 per m2 = 396×9.50 = Rs.3762


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