Question

The diameter of a roller is 42 cm and its length is 60 cm. It
takes 1000 complete revolution to move once over to level a
playground. Find the area of the playground in m2

Answer 1

Diameter of roller = 42 cm = 0.42 m

Radius (r) = 21 cm = 0.21 m

Length/Height of cylindrical roller (h) = 60 cm = 0.6 m

Lateral Surface Area of cylindrical roller = 2πrh

= 2 x 22/7 x 0.21 x 0.6

= 2 x 22 x 0.3 x 0.6

= 7.92 $m^2$

Total revolutions taken to level entire playground = 1000

Total area covered = (1000 x 7.92)$m^2$ = 7920 $m^2$

Hope it helped