Question

A circle of radius $4cm$ is cut out from a square sheet of $12cm$. Find the area of the remaining sheet. Also, find the cost of whole sheet at $Rs8perc{m}^2$. (Use $\pi =3.14$).

Answer 1

$r=4cm$

$\Rightarrow$ Square sheet side $=12cm$

Area of square sheet $={12}^2$

$=144sqcm$

$\Rightarrow$ Circle area $=\pi r^2$

$=\frac{22}{7}\times 4\times 4$

$=\frac{352}{7}sqcm$

$\Rightarrow$ Remaining area $=144-\frac{352}{7}$

$=\frac{1008-352}{7}$

$=\frac{656}{7}sqcm$

$\Rightarrow$ Cost of whole sheet $=Rs8/c{m}^2$

$=8\times 144$

$=Rs.1152$

Hence, the answer is $1152.$