A road roller takes 750 complete revolutions to move once over to level a road. Find the area of the road if the diameter of a road roller is 84 cm and length is 1 m.
Given: Diameter of road roller = 84 cm
∴ Radius of road roller = 42 cm
Length of road roller, h = 1 m = 100 cm
Curved surface area of road roller = 2 π r h
= 2 × 22/7 × 42 × 100
= 26400 cm2
Area covered by road roller in 750 revolutions = 26400 × 750
= 1,98,00,000 cm2 or 1980 m2
∴ the area of the road is 1980 sq. m.