Question

I need to a paint a spherical storage tank in the pool. it has a radius of 8 feet and the paint cans i brought will cover 75 square feet of the surface area. how many cans of paint will i have to buy?

Answer 1

Answer:   11 cans

======================================================

Explanation:

SA = surface area of the sphere

SA = 4*pi*r^2

SA = 4*pi*8^2

SA = 804.247719

The surface area is roughly 804.247719 sq ft.

I used the calculator's stored version of pi to get the most accuracy possible.

Since 1 paint can covers 75 sq ft, divide that surface area over 75 to find out how many cans you need.

804.247719/75 = 10.72330292

Round up to the nearest integer to get 11

You'll have leftover paint, but it's better to go over the goal than come up short.