Q14 of 62 Page 22

The diameter of a roller is 84 cm and its length is 120 cm. It takes 500 complete revolutions moving monce over to level a playground. What is the area of the playground?

Given,


Diameter of roller = 84 cm


Radius of roller =


Length of roller = 120 cm


So,


Curved surface area of roller =


No. of revolution it takes to leve


Hence,


Area of play ground = 500 × 31680 = 15840000 cm2 = 1584 m2


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