MGMAT question in question.

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MGMAT question in question.

by yumi2012 » Tue Aug 06, 2013 6:02 pm
Q#6 on page 99 from Manhattan GMAT book#1 "Fractions&Decimals,Percents"

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 together?

a. 16/3b
b. 17/4b
c. 13/4b
d. 19/12b
e. 7/12b

-------------------

I chose answer "b".. and my equation was "b+3b+1/4b=total". However, the solution page of the book indicates answer "c" Am I wrong? or the book?
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by [email protected] » Tue Aug 06, 2013 6:15 pm
Hi yumi2012,

With these types of questions, you can often TEST values and quickly find the correct answer.

Let's pick
Bradley = b = 4 games
Andrew = 12 games
Charlie = 1 game
Total = 17 games

Now, plug b = 4 into the answers

The correct answer IS B.

The solution listed in the book is incorrect.

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by melguy » Tue Aug 06, 2013 7:56 pm
Hi Rich

Thanks for the explanation. I do not understand the answer choices. If we plug plug b = 4 into the answers the answer will be 17/16 but the answer should be an integer?

Thanks

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by [email protected] » Tue Aug 06, 2013 8:14 pm
Hi melguy,

The "b" in each of the answers is NOT actually in the denominator; I know that that isn't clear from the text in the original post. The answers should be viewed in this way:

A. 16b/3
B. 17b/4
C. 13b/4
D. 19b/12
E. 7b/12

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by iamsaipavan » Tue Aug 06, 2013 8:23 pm
The answer is b

All other entities need to be converted with respect to Bradley's(b)
Andrew(a) = 3b
Charlie(c) b/4
total = a+b+c = 3b+b+(b/4)