if henry were to add 9 gallons of water to a tank that is already 3 / 4 full of water , the tank would be 7 / 8 full . how many gallons of water would the tank hold if it were full ?
n0 = 9.0
n1 = 3.0
n2 = 4.0
n3 = 7.0
n4 = 8.0
t0 = n3 / n4
t1 = n1 / n2
t2 = t0 - t1
t3 = 1.0 / t2
answer = n0 * t3
print(answer)