Question

Find the cost of a polishing a circular table-top of diameter $1.6m$, if the rate of polishing is $Rs15/m^2$. (Take $\pi =3.14$).

Answer 1

The diameter of circular table-top is $1.6m$, then the radius of thetable-top will be $\frac{1.6}{2}m$.

The area of the circular table-top is,

$A=\pi r^2$

$=3.14\times {\left(\frac{1.6}{2}\right)}^2$

$=2.0096m^2$

The rate of polishing $1m^2$is $Rs15$.

The rate of polishing $2.0096m^2$ is $Rs15\times 2.0096=Rs30.144$.