GMAT Prep ?? (Variables)

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GMAT Prep ?? (Variables)

by dferm » Sun May 04, 2008 11:34 am
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 $.018 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

Please explain...

Thanks.

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by Sunny22uk » Sun May 04, 2008 12:38 pm
The gas price/gallon for the state is p. As per the question, it is equal to sum of 2 things:-
1)a 4 percent sales tax to the dealer's price per gallon d, in dollar
Which can be rewritten as d+4%d=d+.04d=1.04d
2)Gasoline tax of $.018 per gallon

the equation becomes p= 1.04d+.018
since we have to find d, we can rewrite the equation as:-
d=p-.018/1.04

Hope this helps.

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Still lost

by vladmire » Sun Nov 30, 2008 6:57 pm
Can anyone explain how to rewrite the equation step by step I came up with d = p/1,04-.018

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by dmateer25 » Sun Nov 30, 2008 7:06 pm
Okay.

The price per gallon at the pump = p

The dealer's price per gallon = d

The sales tax is 4% per gallon

The gasoline tax is .18 per gallon

As per the question, the price per gallon at the pump = 1.04 x the dealers price per gallon + .18

So to shorten this is looks like this:

p=1.04d + .18

p - .18=1.04d

(p - .18)/1.04 = d

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by thinktank08 » Wed Apr 10, 2013 10:18 am
Hey !
I got this Q on my GMAT prep today, i chose
p=d +0.22.

This is how i went about it
p=0.04 + d + 0.18

Could you plz explain to me what my expression means and how is it supposed to be 1.04 instead ??
Would be of great help

Thanks
TT

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by GMATGuruNY » Wed Apr 10, 2013 11:25 am
dferm wrote: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
Let d=100.
Since the price includes a sales tax of 4% and a gas tax of $0.18, we get:
p = 100 + .04(100) + .18 = 104.18.

Thus, when p = 104.18, d=100.
Scanning the answer choices, we should see that D is the most likely to be correct, since it subtracts 0.18 from the value of p=104.18:
d = (p - 0.18)/(1.04) = (104.18 - 0.18)/(1.04) = 104/(1.04) = 100.

The correct answer is D.
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