Question

An earth was felt throughout a circular area of 1,808.64 square miles. What was the radius of the circular area

Answer 1

$\bf \textit{area of a circle}\\\\ A=\pi r^2~~ \begin{cases} r=radius\\ ------\\ A=1808.64 \end{cases}\implies 1808.64=\pi r^2 \\\\\\ \cfrac{1808.64}{\pi }=r^2\implies \sqrt{\cfrac{1808.64}{\pi }}=r$