When 200 gallons of oil were removed from a tank, the volume of oil left in the tank was 3/7 of the tank's capacity. What was the tank's capacity?

(1) Before the 20 gallons were removed, the volume of oil in the tank was 1/2 of the tank's capacity

(2) After the 200 gallons were removed, the volume of oil left in the tank was 1,600 gallons less than the tank's capacity