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
35