I always look at my gauge and I always seem to get around 75 miles per 1/4 tank. about 90% of the time when I look at the tank marks it almost always reads 75 at 3/4, 150 at 1/2, 225 at 1/4 and about 300 at the last hash mark leaving me about 2 gallons in the tank.
I'll get some differences depending on highway or city driving as well as my heavy foot, but mostly it sticks around those numbers.