IR Question - how to solve

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IR Question - how to solve

by prashanth.guru » Thu Aug 08, 2013 11:40 pm
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Please let me how to solve the question in the attached image to arrive at the ans marked in the squares of each column

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by [email protected] » Mon Aug 26, 2013 2:03 pm
Dear prashanth.guru,
I'm happy to help with this. :-)

We know that r = 5, so this gives us the equation

5 = (4x + 8y)/(x + y)

Multiply both sides by that denominator, (x + y)

5*(x + y) = 4x + 8y
5x + 5y = 4x + 8y
x = 3y

So, we see that x must be three times y. So, start with the smallest y: if y = 21, then x = 3*21 = 63, which is not an option. Next y, y = 32, means x = 3*32 = 96 --- bingo! That's it. OA = {x = 96, y = 32}

Does this make sense?

BTW, you may find this helpful:
https://magoosh.com/gmat/2012/gmat-integ ... ing-ebook/

Mike :-)
Magoosh GMAT Instructor
https://gmat.magoosh.com/