Question

The area of a cd-rom label is 113.04 cm squared. What is its radius?

Answer 1

$\bf \textit{area of a circle}\\\\ A=\pi r^2~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ A=113.04 \end{cases}\implies 113.04=\pi r^2\implies \cfrac{113.04}{\pi }=r^2 \\\\\\ \sqrt{\cfrac{113.04}{\pi }}=r\implies 5.998\approx r$