Real-World Examples

Select an example below to instantly pre-fill the calculator and see all the mathematical relationships in action.

A standard 12-inch pizza. Calculating the area shows you exactly how much pizza you're getting.

A large 16-inch pizza. Notice how the area increases quadratically compared to the 12-inch.

A backyard pool requiring calculation of water surface area for a cover.

A standard United States quarter dollar coin.

A standard adult road bike tire. Finding circumference helps track distance per rotation.

The cross-section of our planet at the equator.

A circular raised garden bed for planting vegetables.

The London Eye, one of the world's tallest observation wheels.