Answer:
x = 3
Step-by-step explanation:
5 = 3x - 4
9 = 3x
As
(g/f)(x) = g(x) / f(x)
Therefore,
18.5 - 6 = 12.5 gallons empty
12.5 / 18.5 = 0.676
0.676 x 100 = 67.6%
Answer: 67.6%