FDP Strategies problem

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FDP Strategies problem

by gmattesttaker2 » Sun Jul 01, 2012 6:34 pm
Hello,

Had a question from MGMAT Guide 1 (5th edition) Page 99:

Bradley owns b video game cartridges. If Bradley's total is one-third the total owned by Andrew and four times the total owned by Charlie, how many video game cartridges do the three of them own altogether, in terms of b?

Answer given is (13/4)b

However, I am getting (17/4)b. My approach is as follows:

Bradley - b
b = (1/3)a (a - Andrew's video game cartridges)
b = 4c (c - Charlie's video game cartridges)

a+b+c = 3b + b + (1/4)b = (17/4)b

I am not sure where I am going wrong. Can you please help? Thanks.

Regards,
Sri
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by theCEO » Sun Jul 01, 2012 7:31 pm
I am getting the same answer you get. (13/4)b is wrong.

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by KapTeacherEli » Mon Jul 02, 2012 12:06 pm
It looks to me like all of your math checks out.

13/4 b is the answer that you would get adding just Andrew and Charlie together. As is often the case with GMAT problems, this one gives you an opportunity to solve for the wrong thing. It's likely that the text of the problem got tweaked slightly after or in parallel to the explanation being written, and the explanation is for the problem without Bradley's total; such errors happen rarely but regularly in many companies' practice material (including our own here at Kaplan!). I recommend PMing one of the MGMAT reps who posts regularly around these forums--I'm sure they'll get the answer corrected ASAP.
Eli Meyer
Kaplan GMAT Teacher
Cambridge, MA
www.kaptest.com/gmat

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by gmattesttaker2 » Mon Jul 02, 2012 12:53 pm
Hello theCEO and Eli,

Many thanks for your prompt replies and for clarifying.

Best Regards,
Sri

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by cursorium » Fri Nov 15, 2013 4:07 am
Wow, I spent almost 30 minutes trying to figure out where's my mistake.
Thank you for letting know this is MGMAT fail

Rgds

Cursorium