Gmat Prep?? (Alex Ratio)

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Gmat Prep?? (Alex Ratio)

by dferm » Thu Aug 28, 2008 8:02 pm
The ratio of the amount of Alex's fuel oil bill for the month of February to the amount of his fuel oil bill for the month of January was 3/2. If the fuel oil bill for February had been $40 more, the corresponding ratio would have been 5/3. How much was Alex's fuel oil bill for January?

A. $240
B. $300
C. $360
D. $450
E. $540

Please help...
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by gmattester » Thu Aug 28, 2008 8:14 pm
IMO A
F/J = 3/2
F+40/J=5/3
J=240
What is OA

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by dferm » Thu Aug 28, 2008 8:39 pm
correct...thanks.

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by mlane25269 » Mon Sep 01, 2008 10:51 am
ok i'm confused on this one...

if:

F/J = 3/2
F+40/J=5/3
J=240

I get:

F+40/J=5/3
which reduces to 9+120=10 if I plug in F=3 and J=2 which would be 119 because 129-10 = 119

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by ddm » Mon Sep 01, 2008 11:10 am
F/J=3/2
--> 2F= 3J
F= 3J/2

F+40/J = 5/3

--> 3(3J/2 + 40) = 5J ( Substituting value F in terms of J)
9J + 240 = 10J

J= 240

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by mlane25269 » Mon Sep 01, 2008 12:15 pm
ahhh that makes sense ddm! Thank you!

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by [email protected] » Sun May 24, 2009 10:00 pm
if you are confused it might be because there were no parenthesis in the above equations that should have been there.

(F+40)/J=5/3

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Re: Gmat Prep?? (Alex Ratio)

by maihuna » Mon May 25, 2009 12:28 am
dferm wrote:The ratio of the amount of Alex's fuel oil bill for the month of February to the amount of his fuel oil bill for the month of January was 3/2. If the fuel oil bill for February had been $40 more, the corresponding ratio would have been 5/3. How much was Alex's fuel oil bill for January?

A. $240
B. $300
C. $360
D. $450
E. $540

Please help...
F/J = 3/2 =>2F=3J
(F+40)/J = 5/3
3F+120 = 5J
3*3/2J + 120 = 5J
9J + 240 = 10J
J=240
Charged up again to beat the beast :)

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by Jeff@TargetTestPrep » Mon Dec 11, 2017 5:40 pm
dferm wrote:The ratio of the amount of Alex's fuel oil bill for the month of February to the amount of his fuel oil bill for the month of January was 3/2. If the fuel oil bill for February had been $40 more, the corresponding ratio would have been 5/3. How much was Alex's fuel oil bill for January?

A. $240
B. $300
C. $360
D. $450
E. $540
We are given that the ratio of the amount of Alex's fuel oil bill for the month of February to the amount of his fuel oil bill for the month of January was 3/2. If F = the amount of the Febuary fuel bill and J = the amount of the January fuel bill, we can create the following ratio:

F : J = 3x : 2x

We are also given that if the fuel bill for February had been $40 more, the ratio would have been 5/3. We can create the following equation to determine x:

(3x + 40)/2x = 5/3

3(3x + 40) = 10x

9x + 120 = 10x

120 = x

Thus, the fuel bill in January was 2x = 2(120) = 240 dollars.

Answer: A

Jeffrey Miller
Head of GMAT Instruction
[email protected]

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