The diameter and length of a roller are 84cm and 120 cm respectively in how many revolution can the roller level the playground of area 1584 Sq meter

2 answers

408
So in one rotation, the rollers covers
84π*120 cm^2

number of rotations = 1,5840,000 cm^2/(84π*120) cm^2
= 500.2

How did you get 408?