Last visit was: 23 Jul 2024, 13:54 It is currently 23 Jul 2024, 13:54
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
SORT BY:
Date
Tags:
Show Tags
Hide Tags
Math Expert
Joined: 02 Sep 2009
Posts: 94589
Own Kudos [?]: 643356 [1]
Given Kudos: 86728
Send PM
avatar
Intern
Intern
Joined: 03 Sep 2015
Posts: 3
Own Kudos [?]: [0]
Given Kudos: 9
Send PM
Current Student
Joined: 10 Mar 2013
Posts: 359
Own Kudos [?]: 2740 [0]
Given Kudos: 200
Location: Germany
Concentration: Finance, Entrepreneurship
GMAT 1: 580 Q46 V24
GPA: 3.7
WE:Marketing (Telecommunications)
Send PM
avatar
Manager
Manager
Joined: 02 Jul 2015
Posts: 90
Own Kudos [?]: 46 [0]
Given Kudos: 59
Schools: ISB '18
GMAT 1: 680 Q49 V33
Send PM
Re: If x > 2 and y < -2, then which of the following must be true ? [#permalink]
The answer is C

x equals any value from 2 to infinity while y includes values from -2 to -infinity. this value will always be less than zero as their signs will always be different irrespective of values.
avatar
Intern
Intern
Joined: 17 Nov 2008
Posts: 1
Own Kudos [?]: [0]
Given Kudos: 0
Send PM
Re: If x > 2 and y < -2, then which of the following must be true ? [#permalink]
Pick x=3, y = -3
A) x/y > 1 - Incorrect as x/y = -1
B) x/y < -1 - Incorrect as x/y = -1
C) x/y < 0 - Correct. It will hold for all values x > 2 and y < -2 as x/y = -1 < 0
D) x + y > 0 - Incorrect. x + y = 0
E) xy > 0 - Incorrect. XY = -9 which is less than zero.

C should be the answer.
VP
VP
Joined: 13 Apr 2013
Status:It's near - I can see.
Posts: 1467
Own Kudos [?]: 1638 [0]
Given Kudos: 1002
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE:Engineering (Real Estate)
Send PM
If x > 2 and y < -2, then which of the following must be true ? [#permalink]
Bunuel wrote:
If x > 2 and y < -2, then which of the following must be true ?

A) x/y > 1
B) x/y < -1
C) x/y < 0
D) x + y > 0
E) xy > 0

Kudos for a correct solution.


My solution:

Stem says:- x is +ve and greater than 2, y is -ve and less than -2.

A) x/y>1 (can never be greater than 1 as expression will always be negative as y is negative. Not true )

B) x/y < -1 (can be equal to -1 when x is 3 and y is -3. Not true always)

C) x/y < 0 (will always be less than zero as only one value is negative i.e, "y". Always true.

D) x+y>0 (can be equal to zero or less than zero [3+(-3)=0] or [4+(-5)=-1] Not always true)

E) xy>0(As y is negative xy can never be greater than zero. Not true)
avatar
Manager
Manager
Joined: 23 Aug 2012
Posts: 67
Own Kudos [?]: 15 [0]
Given Kudos: 35
Concentration: Technology
GMAT 1: 710 Q47 V40
Send PM
If x > 2 and y < -2, then which of the following must be true ? [#permalink]
I believe the answer is C. Please see below for explanation.

If x > 2 and y < -2, then which of the following must be true ?

if x= 3 and y =-3 and we plug in the numbers we get

A) x/y > 1---------- 3/-3=-1 not true
B) x/y < -1--------- 3/-3=-1 not true
C) x/y < 0---------- 3/-3=-1 a positive number divided by a negative number will always be negative True
D) x + y > 0-------- 3-3=0 not true
E) xy > 0----------- 3*-3<0 not true


Answer C
Senior Manager
Senior Manager
Joined: 31 Jul 2017
Posts: 434
Own Kudos [?]: 450 [0]
Given Kudos: 752
Location: Malaysia
GPA: 3.95
WE:Consulting (Energy and Utilities)
Send PM
Re: If x > 2 and y < -2, then which of the following must be true ? [#permalink]
Bunuel wrote:
If x > 2 and y < -2, then which of the following must be true ?

A) x/y > 1
B) x/y < -1
C) x/y < 0
D) x + y > 0
E) xy > 0

Kudos for a correct solution.


Hi chetan2u & genxer123,

For this question its obvious that the answer will be C. But I am unable to justify why D is wrong even though we can prove that D is wrong by plugging in some numbers. From the given question x > 2 and -2 > y. As I understand we can add and substract inequalities provided we know their sign. So, when we subtract the above two equation we get x + 2 > 2 - y or x+y > 0. Can you please advise where I am wrong in my thinking.
Senior SC Moderator
Joined: 22 May 2016
Posts: 5325
Own Kudos [?]: 35778 [1]
Given Kudos: 9464
Send PM
If x > 2 and y < -2, then which of the following must be true ? [#permalink]
1
Kudos
Expert Reply
rahul16singh28 wrote:
Bunuel wrote:
If x > 2 and y < -2, then which of the following must be true ?

A) x/y > 1
B) x/y < -1
C) x/y < 0
D) x + y > 0
E) xy > 0

Kudos for a correct solution.


Hi chetan2u & genxer123,

For this question its obvious that the answer will be C. But I am unable to justify why D is wrong even though we can prove that D is wrong by plugging in some numbers. From the given question x > 2 and -2 > y. As I understand we an add and substract inequalities provided we know their sign. So, when we subtract the above two equation we get x + 2 > 2 - y or x+y > 0. Can you please advise where I am wrong in my thinking.

rahul16singh28 , you just got a little mixed up about the direction of the sign. (Take comfort: the answer is there because plenty of others will do exactly what you did.)

It looks to me as if you subtracted inequalities with the same sign.
You said you subtracted these: x > 2 and -2 > y
Not allowed. Their signs face the same direction.

We can add inequalities whose signs are the same direction.

We can subtract inequalities whose signs are in opposite directions.

So you can add the two you listed. And: You are adding a negative number (-2) on LHS, i.e., subtraction. 3 + -2 = (3-2) = 1

····· x > 2
(+)-2 > y
------------------------
= x - 2 > 2 + y

Can you take it from there?

If not, you might want to take a look at Bunuel , Tips and Hints on Inequalities

And here, Inequalities Made Easy

Just in case you haven't seen it, the GMATclub Math Book, IS HERE

Does that help? :-)
RC & DI Moderator
Joined: 02 Aug 2009
Status:Math and DI Expert
Posts: 11485
Own Kudos [?]: 34565 [1]
Given Kudos: 325
Send PM
Re: If x > 2 and y < -2, then which of the following must be true ? [#permalink]
1
Kudos
Expert Reply
rahul16singh28 wrote:
Bunuel wrote:
If x > 2 and y < -2, then which of the following must be true ?

A) x/y > 1
B) x/y < -1
C) x/y < 0
D) x + y > 0
E) xy > 0

Kudos for a correct solution.


Hi chetan2u & genxer123,

For this question its obvious that the answer will be C. But I am unable to justify why D is wrong even though we can prove that D is wrong by plugging in some numbers. From the given question x > 2 and -2 > y. As I understand we can add and substract inequalities provided we know their sign. So, when we subtract the above two equation we get x + 2 > 2 - y or x+y > 0. Can you please advise where I am wrong in my thinking.



Already explained above ....
Just remember that you do not know the signs of variables..
So look at the sign and add the greater quantities and add the smaller quantities, ofcourse sum of greater quantities will be MORE than the sum of smaller quantities..
So x>2 and -2>y tells you x ia POSITIVE and y is NEGATIVE..
So 2-y will become a positive value.
GMAT Club Bot
Re: If x > 2 and y < -2, then which of the following must be true ? [#permalink]
Moderator:
Math Expert
94589 posts