Find all School-related info fast with the new School-Specific MBA Forum

It is currently 20 Sep 2014, 16:33

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

if x is not equal to -y is x-y/x+y > 1 1. x>0 2.

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
SVP
SVP
avatar
Joined: 28 Dec 2005
Posts: 1593
Followers: 2

Kudos [?]: 73 [0], given: 2

GMAT Tests User
if x is not equal to -y is x-y/x+y > 1 1. x>0 2. [#permalink] New post 19 Mar 2008, 18:19
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
if x is not equal to -y

is x-y/x+y > 1

1. x>0
2. y<0
Manager
Manager
avatar
Joined: 20 Aug 2007
Posts: 66
Followers: 1

Kudos [?]: 7 [0], given: 0

Re: DS OG [#permalink] New post 19 Mar 2008, 20:01
pmenon wrote:
if x is not equal to -y

is x-y/x+y > 1

1. x>0
2. y<0


Fact 1
if X>0, no conclusions can be made
eg. X = 5 Y = 1 then <1
if X = 5 and Y = -1 then >1

Fact 2
if y<0, no conclusions can be made
eg. Y=-1 X=-5, then <1
if Y=-1 X = 5, then >1

Combined facts: no conclusions can be made
if X = 5 Y = -1, then >1
if X = 5 and T = -10, then <1

Thus, my answer is E
Expert Post
CEO
CEO
User avatar
Joined: 17 Nov 2007
Posts: 3571
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Followers: 364

Kudos [?]: 1795 [0], given: 358

GMAT ToolKit User GMAT Tests User Premium Member
Re: DS OG [#permalink] New post 19 Mar 2008, 20:58
Expert's post
pmenon wrote:
if x is not equal to -y

is x-y/x+y > 1

1. x>0
2. y<0


\frac{x-y}{x+y}=\frac{x+y-2y}{x+y}=1-\frac{2y}{x+y}>1

\frac{2y}{x+y}<0

Now, we can construct our examples:
1. 2y is always negative (2. y<0)
2. a sign of (x+y) depends on relationship between |x| and |y|. if |x|>|y| then (x+y)>0, otherwise, if |y|<|x| then (x+y)<0
3. x=1, y=-10 and x=10, y=-1
4. Therefore, both conditions are insufficient.
_________________

HOT! GMAT TOOLKIT 2 (iOS) / GMAT TOOLKIT (Android) - The OFFICIAL GMAT CLUB PREP APP, a must-have app especially if you aim at 700+ | PrepGame

Director
Director
avatar
Joined: 10 Sep 2007
Posts: 950
Followers: 7

Kudos [?]: 187 [0], given: 0

GMAT Tests User
Re: DS OG [#permalink] New post 19 Mar 2008, 21:04
Given in question that X and -Y are not equal. So X+Y will not be zero. Thereby telling that denominator is not Zero.

We need to find x-y/x+y is greater than 1 or not.

Statement 1:
Tells us x is +ve. But nothing is said about y. Moreover values of x and y are also not mentioned. so question cannot be answered using this statement alone.

Statement 2:
Tells us that y is negative. But nothing is said about x. Moreover values of x and y are also not mentioned. so question cannot be answered using this statement alone.

Combining both statements:
We have x is +ve and y is -ve, which employs x-y (numerator is +ve).
Now coming to denominator x+y. This term can be -ve if |y|>|x|, or this term can be +ve if |x|>|y|.
Since this we do not know what the values of x and y are, so this question cannot be answered.

Answer E.
SVP
SVP
avatar
Joined: 28 Dec 2005
Posts: 1593
Followers: 2

Kudos [?]: 73 [0], given: 2

GMAT Tests User
Re: DS OG [#permalink] New post 20 Mar 2008, 03:10
great, you guys are getting the right answers. here is my question. i initially started off rearranging the stem to make the question simpler. my first step was to cross multiply to get:

x-y > x+y

x-y-x-y > 0

-2y > 0

y < 0

so my answer was B. Where did i go wrong ?
Expert Post
CEO
CEO
User avatar
Joined: 17 Nov 2007
Posts: 3571
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Followers: 364

Kudos [?]: 1795 [0], given: 358

GMAT ToolKit User GMAT Tests User Premium Member
Re: DS OG [#permalink] New post 20 Mar 2008, 03:29
Expert's post
pmenon wrote:
great, you guys are getting the right answers. here is my question. i initially started off rearranging the stem to make the question simpler. my first step was to cross multiply to get:

x-y > x+y

x-y-x-y > 0

-2y > 0

y < 0

so my answer was B. Where did i go wrong ?


Your transition from \frac{x-y}{x+y}>1 to x-y>x+y is wrong.

The correct transition has to be:

x-y>x+y for x+y>0

x-y<x+y for x+y<0

So, You lost important part of the transition :wink:
_________________

HOT! GMAT TOOLKIT 2 (iOS) / GMAT TOOLKIT (Android) - The OFFICIAL GMAT CLUB PREP APP, a must-have app especially if you aim at 700+ | PrepGame

Re: DS OG   [#permalink] 20 Mar 2008, 03:29
    Similar topics Author Replies Last post
Similar
Topics:
If x is not equal to -y is (x-y)/(x+y) >1 1 x>0 2 neeraj.kaushal 10 27 May 2008, 21:19
If x not equal to -y, is... (x-y)/(x+y) > 1? 1) x>0 2) jimmyjamesdonkey 4 25 Apr 2008, 11:29
If x not equal to -y is x-y/x+y > 1? 1. x > 0 2. y axl_oz 8 14 Jan 2007, 08:47
If x not equal to y , is x-y/x+y > 1 ? 1. x > 0 2. y yezz 9 09 Aug 2006, 12:57
if x is not equal to -y, is (x-y)/(x+y) > 1? 1) x>0 2) joemama142000 5 18 Dec 2005, 12:46
Display posts from previous: Sort by

if x is not equal to -y is x-y/x+y > 1 1. x>0 2.

  Question banks Downloads My Bookmarks Reviews Important topics  


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

Powered by phpBB © phpBB Group and phpBB SEO

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®.