What is an equivalent ratio to 8:20 and
2:5?

4:10.

Step-by-step explanation:

4:10 would be one.

The total surface area is 259.05 ft^2

Step-by-step explanation:

We need to find the surface area of a cylinder

SA =2pi r^2 + 2 pi rh

We need the radius = d/2 = 1/2 = .5

Substituting into the equation

SA = 2 * pi (.5)^2 + 2 pi (.5)7

SA = 2 pi (.25) + 2 pi 3.5

SA =7.5 pi

SA = 7.5*3.14

    =23.55

We have  11 posts that we need to paint, so we must multiply the surface area of one post times 11 posts

23.55*11=259.05

The total surface area is 259.05 ft^2

We cannot answer how much paint, because we are not given that information.  We can only tell you how much surface area there is for the 11 posts.