Check the picture below.
[tex]\bf \textit{volume of a cone}\\\\ V=\cfrac{\pi r^2 h}{3}~~ \begin{cases} r=radius\\ h=height\\[-0.5em] \hrulefill\\ r = 4\\ h = 9 \end{cases}\implies V=\cfrac{\pi (4)^2(9)}{3}\implies V=48\pi \\\\\\ \stackrel{\textit{and 75\% of that will just be }\frac{3}{4}\textit{ of it}}{48\pi \cdot \cfrac{3}{4}\implies 36\pi \quad \approx \quad 113.097}[/tex]
