Surface Area

Question

A swimming pool is 15 by 30 feet and a consistent 5 feet deep. You are painting the walls and floor of the pool. If a gallon can of paint covers 250 square feet, how many gallon cans would you need to buy?

 

Also: You need to fill the pool with water. If 1 cubic foot equals 7.48 gallons of water, how many gallons will it take to fill the pool

Answer 1

You have a rectangular pool  15 X 30 X 5 feet

 

The floor of the pool is 15X30 = 450 ft²

Two sides are 5X15 = 2(75) = 150 ft²

Two sides are 5X30 = 2(150) = 300 ft²

 

Total area to be painted:  900 ft²

 

(900 ft²)/(250 ft²/gal) = 3.6 gallons

Since we can't purchase .6 gallons we

must purchase 4 gallons of paint

 

The volume of the pool is 15X30X5 = 2250 ft³

1 ft³ = 7.48 gallons

2250(7.48) = 16,830 gallons of water