Question

The diameter of a semicircle is 16 miles. What is the semicircle's perimeter?

d=16 mi

Use 3. 14 for ​.


Please help.

Answer 1

$\textit{circumference of a semi-circle}\\\\ C=\pi r~~ \begin{cases} \stackrel{\textit{half diameter}}{r=radius}\\[-0.5em] \hrulefill\\ r=8 \end{cases}\implies C=\pi (8)\implies \stackrel{using~\pi =3.14}{C=25.12}$