The diameter of a roller is 84 cm and its length is 120 cm. It takes 500 completerevolutions to move once over to level a playground. Find the area of the playgroundin `m^2`.

Explanation

Length of the roller, h = `120 cm`
Roller is of from cylinder
Radius=`(diameter)/2 = 84/2 =42`
Area of roller=Curved surface of cylinder
`2pirh`
`(2xx22/7xx42xx120)cm^2`
`31680cm^2`
Area of the playground = Area leveled by the cylinder in `500`
` 500 xx 31680cm^2`revolutions
`15840000 cm^2`
`(15840000)/(10000) m^2 ......(Since 1cm^2 = 1/10000 m^2)`
` 1584 m^2`