# What is Volume?

### Want to learn about volume?

## What is Volume?

Volume is the quantity of three-dimensional space enclosed by a closed boundary. __How does it work? __Volume has different types of formulas for several different shapes. For example for all prisms and cylinders the formula is Base x height. I capitalized the “B” for base because this means: area of the base shape. If you have a triangular prism for instance, the formula would be __B__ase x height /2. For prisms the name will always be the base of that figure. Like a TRIANG-ular prism will always have the base of a triangle.

Ex: If it is lying on its side but the shaded triangles are it's base if you flip it to its long side. (Picture Above)

## Formulas?

**The volume for a cylinder is completely different than prisms. It actually involves pi. Pi is just the ratio of a circle’s circumference to its diameter. Pi is equal to 3.1415926536, but we round it up to 3.14. The formula for a cylinder (or circle) is (Pi) x r (radius) 2 (squared). So here’s an example, if there’s a circular fountain w/ the diameter of 24ft. What’s the area? 24/2=12 (radius). So you take your radius (12) and square it, so you multiply 12x12=144 and multiply it by pi (3.14). Multiply 144 by 3.14 so the answer is 452.16.**