Problem Solving

In a certain state gas stations compute the price p per gallon in $ by adding addin 4% sales to the dealers price per gallon d, in $, and then adding $0.18 per gallon. Which gives the dealers price d in terms of p charged at the pumps?

a)d=p-0.22
b)d=p/1.22
c)d=(p/1.04)-.18
d)d=p-0.18/1.04
e)d=p-0.04/1.18

OA is D. Ive tried working this out but I seem to be missing a step...

p=d+0.04d+0.18;
p=1.04d+0,18;
p-0.18=1.04d;
d=(p-0.18)/1.04

p=d+0.04d+0.18;
p=1.04d+0,18;
p-0.18=1.04d;
d=(p-0.18)/1.04

p = 1.04 d + .18


=> p- 0.18 = 1.04 d

=> d = (p- 0.18) / 1.04