Problema Solution

A grain silo consists of a cylindrical main section and a hemispherical roof. The cylindrical part is 30 ft tall. Express the total volume of the silo (including the part inside the roof section) as a function of the radius of the silo.

Answer provided by our tutors

The total volume of the silo is a sum of


V1 = the volume of the cylinder with radius 'r' and height 30 ft and

V2 = the volume of a half sphere with radius r that makes the hemispherical roof


Volume of the cylinder V1 = (r^2) * pi * h where h = 30 ft, that is V1 = 30 pi * (r^2)


Volume of half sphere with radius r is V2 = 0.5 * (4/3) * pi * (r^3)


The total volume of the silo is


V = V1 + V2


V = 30 pi * (r^2) + 0.5 * (4/3) * pi * (r^3)



V = 30 pi * (r^2) + (2/3) * pi * (r^3) - is a function of the radius of the silo r.