Question

The volume of a cylinder is 90pi units cubed. what is the radius if the height is 10 units

Answer 1

Given the volume of cylinder is 90pi units cubed.

We know the relation for volume of cylinder as,

$\begin{gathered} V=\pi R^2H \\ 90\pi=\pi R^2\times10 \\ \frac{90\pi}{\pi}=R^2\times10 \\ R^2=\frac{90}{10} \\ R^2=9 \\ R=\pm3\text{ units.} \\ \text{Taking only positive value R=3 units.} \end{gathered}$

Hence, the radius is equal to 3 units.