Ernie is making a cylinder-shaped container to store his pens. The container has a base on one end and an opening on the other end. He is going to spray paint the outside of the container. The container has a diameter of 3 inches and a height of 18 inches.

For this case we must calculate the surface area of the container to know the amount of paint that Ernie must use.

We have then:

A = pi * r ^ 2 + 2 * pi * r * h

Where,

r: cylinder radius

h: cylinder height

Substituting values:

A = 3.14 * (3/2) ^ 2 + 2 * 3.14 * (3/2) * 18

A = 176.625 in ^ 2

Answer:

The amount of paint needed is:

A = 176.625 in ^ 2