Asoccer ball made of leather 1/81/8 in thick has an inner diameter of 8.58.5 in . use the formula v=(4/3)πr3v=(4/3)πr3 to calculate the volume. model the ball as a hollow sphere and estimate the volume of its leather shell.

1/8 inch thick
inner diameter of 8.5

volume shell=volume total-volume shell

1/8=0.125

diameter/2=radius
radius inner=8.5/2=4.25
radiustotal=inner+outer=4.25+0.125=4.375

so

Vouter-Vinner=(4/3)pi4.375³-(4/3)pi4.25³
Vshell=(4/3)(pi)(4.375³-4.25)
Vshell=(4/3)(pi)(83.740234375-76.765625)
Vshell=(4/3)(pi)(6.974609375)
Vshell=9.299479166666666666666pi cubic inches
Vshell≈16.433536180619 cubic inches