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Alternative solutions to OG 13

Problem Solving — algebra and arithmetic
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by lotary » Tue Sep 23, 2014 6:14 pm
Hi,

I have a question about the solutions provided in the OG 13

I am middle of practicing math questions and realized the some solutions provided in the book is not using the most efficient way, instead is the long way to solve the problem.

Such as some solutions to the DS questions.

ie. DS 118. Solution provided at the back is long way of solving it VS. what i think is to prove the two triangles are similar triangles is enough

is there a place provided solutions to the OG 13 question with the most effective way?

thanks alot.
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Source: — Quantitative Reasoning |

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by Brent@GMATPrepNow » Tue Sep 23, 2014 6:27 pm
You're absolutely right; the solutions in the OG are not always the most efficient approach.
Is there a place provided solutions to the OG 13 question with the most effective way?

Determining which approach is the most effective is pretty subjective. That said, one of the great things about the BTG forums is that you can see a variety of approaches to a question. It's up to you to determine which approach is most effective for you.

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by [email protected] » Tue Sep 23, 2014 6:45 pm
Hi lotary,

Brent is absolutely correct - these Forums serve as a great source to learn many different ways to solve GMAT questions. You should feel free to post any questions that you're curious about (from the OG13 or any other source); the Experts and other Users will likely provide you with a variety of approaches as well as additional insights, tips and suggestions that will help you to improve.

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by GMATGuruNY » Tue Sep 30, 2014 2:57 am
lotary wrote:Hi,

I have a question about the solutions provided in the OG 13

I am middle of practicing math questions and realized the some solutions provided in the book is not using the most efficient way, instead is the long way to solve the problem.

Such as some solutions to the DS questions.

ie. DS 118. Solution provided at the back is long way of solving it VS. what i think is to prove the two triangles are similar triangles is enough

is there a place provided solutions to the OG 13 question with the most effective way?

thanks alot.
I suspect that you are referring to either DS113 or DS119.
I posted solutions for these problems here:
https://www.beatthegmat.com/data-suffici ... 85748.html
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My students have been admitted to HBS, CBS, Tuck, Yale, Stern, Fuqua -- a long list of top programs.

As a tutor, I don't simply teach you how I would approach problems.
I unlock the best way for YOU to solve problems.

For more information, please email me (Mitch Hunt) at [email protected].
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