a cylinder and a cone have the same height, but the base radius of the cylinder is only 1/3 of that cone. If the volume of the cylinder is 7, then what is the volume of the cone?
If the volume of the cylinder is 7, then what is the volume of the cone?
Hello Guest!
\(r_{cyl}=\dfrac{r_{con}}{3}\\ V_{cyl}=pi (\dfrac{r_{con}}{3})^2h=7\\ \dfrac{(r_{con})^2}{9}=\dfrac{7}{\pi h}\\ \color{blue}(r_{con})^2=\dfrac{63}{\pi h}\)
\(V_{con}=\dfrac{1}{3}\pi h\cdot (r_{con})^2=\dfrac{1}{3}\cdot \pi h\cdot \dfrac{63}{\pi h}=\dfrac{63}{3}\\ \color{blue}V_{con}=21\)
The volume of the cone is 21.
!