Volume of a right circular cylinder

How to use it

1. 1Halve a given diameter first; the formula takes the radius.
2. 2Where $r$ and $h$ are given as a ratio, write both through one multiplier $k$ so that the volume becomes a single cubic in $k$.
3. 3Take $\pi =\frac{22}{7}$ when a radius is a multiple of $7$, which is what makes these volumes come out whole.

Step-by-step

1. 1
   $V=\frac{22}{7}\times 7^2\times 5$

   Why: The $7$ in the radius cancels the denominator of $\pi$.

2. 2
   $=22\times 7\times 5=770$ m${}^3$