It is currently 20 Nov 2017, 20:20

Close

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

For a finite sequence of nonzero numbers, the number of

  post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Manager
Manager
avatar
Joined: 05 Aug 2008
Posts: 91

Kudos [?]: 47 [0], given: 0

Schools: McCombs Class of 2012
For a finite sequence of nonzero numbers, the number of [#permalink]

Show Tags

New post 03 Jan 2009, 22:12
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

For a finite sequence of nonzero numbers, the number of variations in sign is defined 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 ?

(A) One
(B) Two
(C) Three
(D) Four
(E) Five


Attachment:
Q1.JPG
Q1.JPG [ 29.72 KiB | Viewed 980 times ]

Kudos [?]: 47 [0], given: 0

Manager
Manager
avatar
Joined: 05 Aug 2008
Posts: 91

Kudos [?]: 47 [0], given: 0

Schools: McCombs Class of 2012
Re: Consecutive Numbers [#permalink]

Show Tags

New post 04 Jan 2009, 14:36
it is, can you explain how you arrived at that solution?

thanks

Kudos [?]: 47 [0], given: 0

Manager
Manager
User avatar
Joined: 30 Dec 2008
Posts: 121

Kudos [?]: 32 [0], given: 0

Re: Consecutive Numbers [#permalink]

Show Tags

New post 04 Jan 2009, 16:49
you add the count.. if the product of the 2 consecutive numbers = negative.
here are the possibilities:
1st term x 2nd term = negative... that's 1
2nd term x 3rd term = negative... that's 2
3rd x 4th = positive
4th x 5th = negative..that's 3
5th x 6th = positive

so your answer is 3.

Kudos [?]: 32 [0], given: 0

Senior Manager
Senior Manager
avatar
Joined: 23 May 2008
Posts: 414

Kudos [?]: 468 [0], given: 14

Re: Consecutive Numbers [#permalink]

Show Tags

New post 05 Jan 2009, 03:11
answer is C
multiply the consecutive numbers and count when the sign of the multiplied number is negative.

Kudos [?]: 468 [0], given: 14

Manager
Manager
avatar
Joined: 05 Aug 2008
Posts: 91

Kudos [?]: 47 [0], given: 0

Schools: McCombs Class of 2012
Re: Consecutive Numbers [#permalink]

Show Tags

New post 05 Jan 2009, 11:48
thanks for your detailed explanation cul3s.

When I first encountered this question I re-organized the numbers in order of magnitude, when I should of just used them the way they were given. I got misled since it says "consecutive"

thanks again.

Kudos [?]: 47 [0], given: 0

Re: Consecutive Numbers   [#permalink] 05 Jan 2009, 11:48
Display posts from previous: Sort by

For a finite sequence of nonzero numbers, the number of

  post reply Question banks Downloads My Bookmarks Reviews Important topics  

Moderator: chetan2u



GMAT Club MBA Forum Home| About| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.