In a certain state, gasoline stations compute the price per gallon p, in dollars, charged at the pump by adding a 4 percent sales tax to the dealer’s price per gallon d, in dollars, and then adding a gasoline tax of $0.18 per gallon. Which of the following gives the dealer’s price per gallon d in terms of the price per gallon p charged at the pump?
A. d=p-0.22
B. d=p/1.22
C. d=(p/1.04)-0.18
D. d=(p-0.18)/1.04
E. d=(p-0.04)/1.18
Answer D.
Can you please go through this?