1.37 gallon of paint covers the wall area of 10.8 ft long and 16.4 ft wide. How thick is the paint in mm?

Can someone please explain to me how to go about solving this problem without actually solving it for me? That'd be wonderful!





I already tried using 1.37 gallons as the volume and then using doing length, width, and height and trying to figure it out from there and it was wrong. So any help would be wonderful!1.37 gallon of paint covers the wall area of 10.8 ft long and 16.4 ft wide. How thick is the paint in mm?
It's hard to show how without actually solving it, but here goes:





You can do this all in English units (gallons and inches / feet) and then convert to mm at the end, or you can convert to metric along the way.





I'll do it the second way.





First convert 1.37 gallons to metric.


1.37 gallons = approx 5 liters (very rough approximation,


use a better one.)





Forging ahead with our bad approximation:


5 liters = 5000 cubic cm = 5000 x 10 x 10 x 10 cubic mm





Then you must convert 10.8 x 16.4 sq ft to metric.


Total area is about 175 sq ft (again, a poor estimate)





1 sq ft = approx 30x30 cm^2 = 300x300 mm^2 (again, 30 is a rough approximation, use a better number)





So divide the volume of paint by 175 x 90000 mm^2 to get the thickness.





Remember to use the not-so-round, but better conversion factors.





You can check you actual answer against the amazing Google:


where the calculator can do this in one shot:





(1.37 US gallons) / ((10.8 feet) * 16.4 feet) = 0.31516 millimeters





It accepts ';1.37 gallons / (10.8 feet * 16.4 feet) in mm'; in its search box, and returns the whole equation.





';Back in my day, we had to carve problems into stone with a chisel, and we didn't even have a hammer ...';