Register    Login    Search    Rss Feeds

Forums Home » Ask An Instructor » GMAT Math » GMAT Prep Math


 Page 1 of 1 [ 2 posts ] 



  Print view Print view Previous topic Previous topic | Next topic Next topic
 

Number of variations in Signs

Author Message
shrads.jp
 Post subject: Number of variations in Signs
 Post Posted: Thu Dec 17, 2009 1:47 pm 
Offline
Students


Posts: 11
I faced the below sum in GMAT Prep yesterday...pls help as i have my exam this week...
i cudnt understand the language of the sum :-((

For a finite sequence of nonzero numbers , the number of variations in sign is designed as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence 1, -3 ,2, 5, -4 ,-6?
1) One
2) Two
3) Three
4) Four
5) Five
OA 3
Top 
RonPurewal
 Post subject: Re: Number of variations in Signs
 Post Posted: Sat Jan 09, 2010 5:04 am 
Offline
ManhattanGMAT Staff


Posts: 7146
shrads.jp wrote:
I faced the below sum in GMAT Prep yesterday...pls help as i have my exam this week...
i cudnt understand the language of the sum :-((

For a finite sequence of nonzero numbers , the number of variations in sign is designed as the number of pairs of consecutive terms of the sequence for which the product of the two consecutive terms is negative. What is the number of variations in sign for the sequence 1, -3 ,2, 5, -4 ,-6?
1) One
2) Two
3) Three
4) Four
5) Five
OA 3


see here:
for-a-finite-sequence-of-non-zero-numbers-the-number-t7396.html

just decode the problem -
the number of pairs of consecutive terms --> two terms that appear next to each other (YOU ARE NOT ALLOWED TO RE-ORDER THE TERMS)
... for which the product of the two consecutive terms is negative --> this happens when THE TWO TERMS HAVE OPPOSITE SIGNS.

but yeah - the primary challenge here definitely lies in understanding what's going on in the first place.
Top 
Display posts from previous:  Sort by  
 
 Page 1 of 1 [ 2 posts ] 





Who is online

Users browsing this forum: No registered users and 0 guests

 
 

 
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to: