Question

The diameter of a roller is 2.5 m and its length is 1.4 m how much area will it cover in 77 revolution?

Answer 1

D= 2.5, h = 1.4= 7/5
Area covered in one rotation = 2 * pi * r * h
= 2*22/7*2.5/2*7/5
Area covered in 77 rotations...
Area × 77
= 847 m square