When you study mathematics, it can be helpful to use familiar objects to understand how to solve a problem. For example, you might need to learn how to calculate the volume of a sphere. It's likely that you have access to a commonly available sphere, like a baseball. You might be tempted to fill a large measuring cup with water and submerge the ball to see how much the water rises, which would tell you the sphere's volume but ruin the baseball. To keep the ball dry, you can do calculations that also enable you to find the volume of spheres larger than your biggest measuring cup.
Measure the baseball from edge to edge with a ruler to get its diameter.
Divide the diameter in half to get the radius. According to The Physics Factbook online, the standard diameter for a baseball is about 7.3 centimeters. The radius would be 3.65 centimeters.
Find the volume of the baseball by using the formula 1.33 times pi times the radius cubed. In this case, you multiply 1.33 times pi (3.14) to get 4.1762. Cube the radius (3.65 times 3.65 times 3.65) to get 48.627.
Multiply 4.1762 times 48.627 to get a volume of 203.076 cubic centimeters.