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Gmat Prep 1 - DS Odd/Negative Set problem

by GMAT Fever Thu Apr 10, 2008 8:32 pm

I was a bit confused on this one, any help would be appreciated on how to break down each of these statements.

If M is a finite set of negative integers, is the total number of integers in M an odd number?

(1) The product of all the integers in M is odd

(2) The product of all the integers in M is negative.
GMAT Fever
 
 

by GMAT Fever Thu Apr 10, 2008 8:37 pm

NM, I answered my own question, I know what I did wrong now. See people paying attention to detail is so key!

If M is a finite set of negative integers, is the total number of integers in M an odd number?


I had initially picked C, but after picking up that the set is of negative integers it make perfect sense why B is the answer.

(1) The product of all the integers in M is odd
Can be Odd X Odd or Odd X Odd X Odd, even or odd number of integers in the set NS

(2) The product of all the integers in M is negative.
This can only occur when the number of items in the set are odd (Neg X Neg X Neg), even number of items (Neg X Neg) yields a positive number

Correct Answer is B[/quote]
rfernandez
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by rfernandez Fri Apr 11, 2008 4:11 am

Nice work.

Rey