# Prisms and pyramids

**Prisms**

A **prism** is a 3-D shape that has a constant cross-section along its length. The volume of a prism is calculated using the following formula where *A* is the cross section, *l* is the length and *h* is the height.

Volume = A*h*

Volume = A*l*

**Pyramids**

A **pyramid** is a 3-D shape with a base which is usually a polygon but can also be a shape with curved edges. The it also has faces rising up from the base meet at a common vertex or **apex**. The most common pyramids are tetrahedron, square based pyramid and cone.

The volume of a pyramid is calculated using the following formula, where *A* is the base area and *h* is the height.

Volume of a pyramid = 1/3*Ah*