Volume and Surface Area

Question

A farmer's silo is in the shape of a cylinder topped by a hemisphere. If the radius of the silo is 15 ft and the height of the cylindrical portion is 47 ft, what is the volume of the silo? 

Answer 1

Hey Fay,

It helps visualizing this question if you think of the silo as a cylinder and a hemisphere and finding the volumes of each separately.

In this way you have a cylinder with radius 15ft and length 47 ft and a hemisphere (half of a sphere) with radius 15ft.

Apply volume formulas for each :

V(cylinder)= Pi * length * r^2

V(sphere)= 4/3* Pi * r^3 - since you have hemisphere use V(hemisphere) = 4/6 * Pi * r^3

Plug in the values for r and length.

In the end add them up.

Let me know if you have any questions.