Question

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`.

Answer 1

r=42cm
l=120cm
Area rolled in one revolution=`2pirl`
=`2*22/7*42*120`
=`31680cm^2`
Area of playground=500*31680`cm^2`
=`1584*10^4cm^2`
=`1584m^2`.