Number properties

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Number properties

by petud » Mon Mar 30, 2015 2:03 am
Hi,

A=-B

1. A is positive.
2. (A+B)^{2} is positive.

THe answer is meant to be B.

Could someone please walk me through the answer?

Thanks!!

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by DavidG@VeritasPrep » Mon Mar 30, 2015 2:10 am
I'm assuming the original question was "Is A = - B?"

You could add 'B' to both sides so that the rephrased question is "Is A + B = 0?"

S1: tells us nothing about B, so Not Sufficient.

S2: If (A + B)^2 is positive, we know that A + B is positive. If A + B is positive, we know that it isn't equal to 0. Because we know definitively that the answer to the question is "NO,' this statement alone is Sufficient.
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by petud » Mon Mar 30, 2015 2:32 am
THank you David! I need to get used to data sufficiency questions!! I was answeirng NO and nto suff and the same time!!

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by [email protected] » Mon Mar 30, 2015 10:32 am
Hi petud,

DS questions are unique to the GMAT; most Test Takers need time to learn the format and the logic behind these types of questions, so what you're experiencing is quite common. Thankfully, there are patterns to DS questions and tactics that you can repeatedly use to get to the correct answer. You just need the proper practice materials and study time.

How long have you been studying?
What resources have you been using?

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by Brent@GMATPrepNow » Tue Mar 31, 2015 9:42 am
petud wrote:THank you David! I need to get used to data sufficiency questions!! I was answeirng NO and nto suff and the same time!!
You're not alone; EVERYONE struggles with Data Sufficiency (DS) questions at first. Keep in mind that this question type is unique to the GMAT, so it's totally foreign territory.

It just takes time for the concepts and strategies to become secondary, at which point you may come to find that DS questions are actually easier than Problem Solving questions.

I could start listing dozens of DS strategies and common mistakes (like confusing the answer to sufficiency question to the answer to the target question), but it's easier to just direct you to our free set of videos that cover everything you need to know to tackle DS questions: https://www.gmatprepnow.com/module/gmat-data-sufficiency

Cheers,
Brent
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by petud » Tue Mar 31, 2015 1:35 pm
Thank you for the link Brent. I will have a look at it.

Rich, I have been studying for two weeks now (although only in the weekends). I just got a magoosh package and a friend of mine lend me some manhattan gmat books.