Three dimensions

Cones

3D shapes with a point means the area will be a third

Area of base = $\pir^2$

Volume of cone = $1/3\times\volume\ of\ a\ cyli\nder$

Volume of cone = $1/3\times \Area\ of\ base\times\ height$

Volume of cone = $1/3\times \pir^2\times\ height$

3 cones make a cylinder if you add them up

3 cones fill 1 cylinder (with the same size base and height).

NOTE:

Areas shaded blue are all equal.