Question

A cubed shaped water tank has a volume of 729 m3 , one of the walls on the inside will need to be painted, a gallon of paint will cover an area of 15 square meters, the paint can only be bought by the gallon (you can’t buy part of a gallon), how many gallons of paint will be needed to paint one of the walls?

Answer 1

Answer: 33 gallons

Explanation:

The water tank is a cube, with one dimension of x meters. Its volume will be x^3.

X^3 = 729m^3

x = 9 meters. The cube has 4 side walls and a top and bottom, for a total of 6 interior walls. Each wall has an area of x^2, or 81 m^2.

(6 walls)*(81 ft^2) = 486 m^2

One gallon of paint will cover 15 m^2. The conversion factor is (1 gallon/15 m^2)

(486 m^2)*(1 gallon/15 m^2) = 32.4 gallons, rounded up to 33 gallons