8th Grade · Geometry
Volume
8.G.C.9
Definition
The amount of three-dimensional space a solid occupies, measured in cubic units. Cylinders, cones, and spheres each have their own volume formula involving pi.
Examples
- Cylinder: V = πr²h.
- Cone: V = (1/3)πr²h. Sphere: V = (4/3)πr³.
Key rule
Cylinder, cone, and sphere all use pi and the radius, but the cone has 1/3 and the sphere uses r cubed.
Memory hook
Space inside a solid, measured in cubic units.