232. In a certain state, gasoline stations compute the price per gallon p, in dollars, charged at the pump by adding a 4% sales tax to the dealer's price per gallon d, in dollars, 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
Solution:
[spoiler]The easiest way to start is to set up the equation in terms of d and p in the way the stimulus presents the question:
p = 1.04d + 0.18
Now solve for d:
p - 0.18 = 1.04d
d = (p - 0.18) / 1.04 (D)[/spoiler]
isn't answer should be : B) d = p/1.22
source: 300+ gmat Q.
i doubt....pl explain.
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The solution is perfectly alright.advita wrote:232. In a certain state, gasoline stations compute the price per gallon p, in dollars, charged at the pump by adding a 4% sales tax to the dealer's price per gallon d, in dollars, 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
Solution:
[spoiler]The easiest way to start is to set up the equation in terms of d and p in the way the stimulus presents the question:
p = 1.04d + 0.18
Now solve for d:
p - 0.18 = 1.04d
d = (p - 0.18) / 1.04 (D)[/spoiler]
isn't answer should be : B) d = p/1.22
source: 300+ gmat Q.
It'd have been easier to help you if you'd have posted your method.
Anyway, as you bold faced $0.18 per gallon and your answer guess contains 1.22 in it, I assume you've added 0.18 with 1.04 and got 1.22. But 1.04 is multiplied with d. You cannot add (1.04d) with 0.18 and get 1.22d! (0.18 is not multiplied with d, it's an independent term.)
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Price per gallon = Dealer's price + 4% of Dealer's price + 0.18RikaMueller wrote:Can you pls explain how you reached to the answer?
=> p = d + 4% of d + 0.18
=> p = d + (4/100)*d + 0.18
=> p = d + (0.04)*d + 0.18
=> p = d*(1 + 0.04) + 0.18
=> p = (1.04)d + 0.18
=> p - 0.18 = (1.04)d
=> d = (p - 0.18)/1.04
The correct answer is D.
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Ah ok, I got that. Was confused with the p - 0.22, and thought that this is the right answer.
Thanks
Thanks