suppose that the gas tank of a car holds 12 gallons and that the car uses 1/ 20 of a gallon per mile .let x be the nuber of miles the car has gone since the tank was filled?
(1/20x)= 12
so now get x by itslef!
(1/20x)/ (1/20)= 12/(1/20)
x= 240!
yeah I am good! that is good! good luck!