Question

find the area of the circle whose circumference is 528​

Answer 1

$\bold \red \star \: \large \underline{Solution:-}$

$circumference \: of \: circle \: = 2 \pi r. \\ \\ 2 \pi r = 528. \\ \\ r = \frac{528}{2 \pi} \\ \\ r = \frac{528 \times 7}{2 \times 22} \\ \\ r = \frac{ \cancel{3656}}{ \cancel{44}}. \\ \\ \red{r = 84. }$

Now,

Radius = 84.

$area \: of \: circle \: = \pi {r}^{2} . \\ \\ \rightarrow \pi {r}^{2} \\ \\ \rightarrow \frac{22}{7} ( {84})^{2}. \\ \\ \rightarrow\frac{22}{ \cancel7} \times \cancel{7,056}. \\ \\ \rightarrow 22 \times 1,008. \\ \\ \rightarrow 22,176.$

The area of circle = 22,176.