Question

26. A silo has a cylindrical storage area topped by half of a sphere. To figure out how much paint it willtake to cover the whole silo, farmer Ted needs to know the surface area of the silo. He knows it is 40feet high and has a radius of 20 feet. What is the surface area (in square feet in terms ofa)?SA = ( 2 x t xrxh) + (2x xr2)

Answer 1

This is a question on geometry. We are told that the said silo is a combination of two shapes, a cylinder and a hemisphere. To find the area of such a shape, we will simply find the areas of the individual shapes and add them up.

This is illustrated below.

The above illustrates a model of the silos with radius 20ft and height 40ft.

The area of the cylinder's surface is:

`A_c=2\pi rh`

where: r = 20ft and h = 40 ft

`A_c=2\pi*20*40=1600\pi`

The area of the hemisphere is:

`A_c=2\pi rh`