How do I calculate how many gallons of water the tank on my trailer holds?
Assuming those measurements are for a rectangular tank, here’s the easy way. Express everything in inches and multiply it together: 72*4*1 = 288 cubic inches Now go to Google and type: 288 cubic inches in gallons And Google will do the unit conversion for you (1.25 gallons). Sorry Yahoo — didn’t mean to pump the competition.