The diameter of a baseball is about 1.4 in.

How much leather is needed to cover the baseball?

How much rubber is needed to fill it?

You need to find the surface area and the volume. The formula for surface area is 4*3.14 (pi) * radius^2 which is equal to 6.5144 inches^2 in this case. The amount of rubber needed to fill it is equal to the volume. The formula for volume of a sphere is 4/3*3.14 (pi) * radius^3, just plug in the number (remember radius is half of diameter) and that will give you the answer!