Q35 of 189 Page 512

The diameter of a roller, 1 m long, is 84 cm. If it takes 500 complete revolutions to level a playground, the area of the playground is

Curved surface area of a cylinder =


1m= 100cm, radius = 42 cm = 0.42m


Curved surface area


Area of the playground = 500 × 2.64 m2 = 1320 m2

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