8th Grade · Geometry

Cone

8.G.C.9

Definition

A three-dimensional solid with a circular base narrowing to a single point. Its volume is (1/3)πr2h.

Examples

  • V = (1/3)πr2h.
  • A cone's volume is exactly one-third of a cylinder with the same base and height.

Key rule

Cone volume is one-third of the matching cylinder's volume.

Memory hook

One-third of a cylinder's volume.