Just for fun....the only accurate way to measure fuel is by weight. Because a Gallon or Litre (are we using imperial gallons or US gallons?)is greater or lesser weight depending on temp. So on a cold day 1kg or 1pound or sheckle could be say 0.9 litres pound or hogs head, while on a hot day it might be 1.2!!

So folks in cold climates go further on a tank of fuel than those in hot climates!!

Now try and figure out quick mental formula for that.