Percentage by which the gas tank of the car is full = 40% Amount of gas in the gas tank = 8 gallons Let us assume the capacity of the gas tank = x gallons Then 40% * x = 8 (40/100) * x = 8 4x/10 = 8 4x = 8 * 10 4x = 80 x = 80/4 = 20 gallons So the total capacity of the gas tank of the car is 20 gallons. I hope the procedure is clear to you.
