posted by Matt .
A gallon of paint can cover an area of 385 square feet. How thick is the coat of paint in inches.
It is not a good question, a gallon of wet paint dries, and the volume shrinks by about one half.
Ignoring that reality, volume of paint is area * thickness
You will have to make some unit conversions. You can check your work by putting this in the Google Search window:
1gallon/385ft^2 in inches