Duplicate Statements

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Duplicate Statements

by Mindoverdoubt » Tue Mar 17, 2015 3:04 am
Hello everyone,

I am currently studying for the GMAT and was informed that in Data Sufficiency if statement 1 and statement 2 are the same then the answer must ALWAYS be either D (either) or E (neither). Is this true?

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by Brent@GMATPrepNow » Tue Mar 17, 2015 6:22 am
Yes, that's true.

Think about it this way: If statement 1 allows you to answer the target question with certainty, and statement 2 provides the same info that statement 1 does, then statement 2 must also be sufficient, which means the answer is D.

Conversely, if statement 1 does NOT allow you to answer the target question with certainty, and statement 2 provides the same info that statement 1 does, then statement 2 must CANNOT be sufficient either. When we combine two identical statements (and each statement is not sufficient), it's still impossible for us to answer the target question.

Example:
Target question: What is the value of positive integer x
Statement 1: (x - 1)(x - 3) = 0
Statement 2: x is a factor of 3
Each statement provides the same information: x = 1 or 3
So, when we COMBINE statements, we don't learn anything new. So, the answer is E
For more on this, please see our free video: https://www.gmatprepnow.com/module/gmat- ... cy?id=1109

Cheers,
Brent
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by DavidG@VeritasPrep » Thu Mar 19, 2015 6:05 am
See here for another good example of a problem in which it will be very helpful to see that the statements are providing the same information: https://www.beatthegmat.com/gmat-prep-ge ... 77074.html
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by Matt@VeritasPrep » Sun Mar 22, 2015 10:12 pm
Mindoverdoubt wrote:Hello everyone,

I am currently studying for the GMAT and was informed that in Data Sufficiency if statement 1 and statement 2 are the same then the answer must ALWAYS be either D (either) or E (neither). Is this true?
This is true, but be careful! A more common setup on the test is two statements that SEEM TO BE identical, but actually are not. (In this scenario, S1 is typically sufficient while S2 has undergone some subtle change to make it insufficient.)