Question

A road roller is cylindrical in shape . Its circular end has a diameter 200 cm and its width it 1.4 m . Find the least number of revolutions that the roller must make in order to level a playground of dimensions $125m\times 20m$.

Answer 1

$h=1.4$m

$r=100$cm$=1$m

CSA$=2\pi rh=2\times \frac{22}{7}\times 1\times 1.4=8.8m^2$

Total area $=125\times 2-=2500m^2$

No. of revolutions $=\frac{2500}{8.8}$

$=284.09$.