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

 It is currently 06 May 2015, 02:41

### 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

# 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:
Director
Joined: 17 Oct 2005
Posts: 940
Followers: 1

Kudos [?]: 63 [0], given: 0

if x is not equal to -y, is (x-y)/(x+y) > 1? 1) x>0 2) [#permalink]  18 Dec 2005, 12:46
00:00

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
Director
Joined: 17 Dec 2005
Posts: 552
Location: Germany
Followers: 1

Kudos [?]: 12 [0], given: 0

[#permalink]  18 Dec 2005, 13:45
Great questions joemama, where have you got them from?

But I can't estimate if they are hard or not.

(x-y)/(x+y) > 1?

x-y > x+y ?

x > x + 2y?

2) Is not sufficient, since we dont know whether x is positive or negative.

1) Is not sufficient, since we don't know if y is positive or negative.

Both together are sufficient, because x > x - 2y, while x > 0

I think it is C
Director
Joined: 17 Oct 2005
Posts: 940
Followers: 1

Kudos [?]: 63 [0], given: 0

[#permalink]  18 Dec 2005, 17:14
allabout, its mostly from gmatprep
Intern
Joined: 18 Nov 2005
Posts: 8
Followers: 0

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

The above reasoning appears incorrect.. [#permalink]  18 Dec 2005, 17:38
There are a couple of flaws in the above reasoning.

if (x-y)/(x+y) > 1

does not imply (x-y) > (x+y) because we do not know whether x+y is positive or negative. x-y > x+y only if (x+y) is positive.

the inequality is reversed if (x+y) is less than zero.

Secondly, in, x > x +2y, can't you cancel x and say 0 > 2y and say the answer is B (not sure why you did not cancel x).

Anyway, the way I would proceed is...

(x-y)/(x+y) ?> 1

write x-y as x+y-2y

hence, (x-y)/(x+y) = (x+y-2y)/(x+y)

= 1 -(2y/(x+y))

hence, the problem boils down to whether 1-(2y/(x+y)) > 1

now you can cancel out 1 and say whether -2y/(x+y) > 0

statement 1: x > 0, say x = 5, then y = 1 and y = -6 gives two different results, hence statement one is not sufficient.

statement 2: y < 0, now if y = 2 say, x = 3 or -3 gives two different results. hence statemet two is not sufficient.

even with both the statements combined together, you can have x = 5 and y = -1 and -6 will give two different results. Hence, in my opinion E is the answer.

-Srinivas (mathguru).
Director
Joined: 17 Dec 2005
Posts: 552
Location: Germany
Followers: 1

Kudos [?]: 12 [0], given: 0

[#permalink]  18 Dec 2005, 23:33
Hey srinivasssrk,

You're right.

The idea to transform (x - y) to (x+ y -2y) is the way we have to go, the basic math transformation, when dealing with such terms.

Good job.
Director
Joined: 26 Sep 2005
Posts: 578
Location: Munich,Germany
Followers: 1

Kudos [?]: 10 [0], given: 0

[#permalink]  20 Dec 2005, 22:21
I got E as well.

srinivas: brilliant expln
allabout : wie geht sie - muenchen ist sehr gut.
[#permalink] 20 Dec 2005, 22:21
Similar topics Replies Last post
Similar
Topics:
If x not equal to -y, is... (x-y)/(x+y) > 1? 1) x>0 2) 4 25 Apr 2008, 11:29
if x is not equal to -y is x-y/x+y > 1 1. x>0 2. 5 19 Mar 2008, 18:19
If x is not equal to -y, is (x-y)/(x+y) > 1? 1) x>0 2) 7 07 Sep 2007, 07:32
If x not equal to -y is x-y/x+y > 1? 1. x > 0 2. y 8 14 Jan 2007, 08:47
If x not equal to y , is x-y/x+y > 1 ? 1. x > 0 2. y 9 09 Aug 2006, 12:57
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

 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®.