Question

The volume of a? cone-shaped hole is 49 pi ft cubed . If the hole is 3 ft? deep, what is the radius of the? hole?

Answer 1

$\bf \textit{volume of a cone}\\\\ V=\cfrac{\pi r^2 h}{3}~~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ h=3\\ V=49\pi \end{cases}\implies 49\pi =\cfrac{\pi r^2(3)}{3}\implies 49\pi =\pi r^2 \\\\\\ \cfrac{49\pi }{\pi }=r^2\implies 49=r^2\implies \sqrt{49}=r\implies 7=r$