Three key volume formulas — one for each curved solid — all built around π and the radius.
The volumes of cylinders, cones, and spheres all involve π and the radius r. Notice that a cone's volume is exactly one-third of the cylinder with the same base and height — a powerful relationship to remember.
A can has radius 3 cm and height 10 cm. V = π(3²)(10) = 90π ≈ 282.7 cm³
A basketball has radius 12 cm. V = (4/3)π(12³) = (4/3)π(1728) = 2304π ≈ 7238.2 cm³
Remember This!
Three cones fit exactly inside one cylinder of equal radius and height. So the volume of a cone is always exactly 1/3 the volume of the enclosing cylinder.
An ice cream cone has radius 4 cm and height 9 cm. What is its volume in terms of π?