[tex]\textit{area of a circular ring}\\\\ A=\pi (R^2-r^2)~~ \begin{cases} R=\stackrel{larger}{radius}\\ r=\stackrel{smaller}{radius}\\[-0.5em] \hrulefill\\ R=50\\ r=36 \end{cases}\implies \begin{array}{llll} A=\pi (50-36)\implies A=14\pi \\\\\\ A\approx 44.0 \end{array}[/tex]
