GMAT Changed on April 16th - Read about the latest changes here

It is currently 21 May 2018, 19:16

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

Is x > y? (1) x= y+2 (2) x/2 = y-1

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

Expert Post
1 KUDOS received
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 45222
Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 02 Jul 2012, 02:39
1
This post received
KUDOS
Expert's post
15
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

69% (00:59) correct 31% (00:58) wrong based on 1085 sessions

HideShow timer Statistics

The Official Guide for GMAT® Review, 13th Edition - Quantitative Questions Project

Is x > y?

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

Diagnostic Test
Question: 37
Page: 25
Difficulty: 550


GMAT Club is introducing a new project: The Official Guide for GMAT® Review, 13th Edition - Quantitative Questions Project

Each week we'll be posting several questions from The Official Guide for GMAT® Review, 13th Edition and then after couple of days we'll provide Official Answer (OA) to them along with a slution.

We'll be glad if you participate in development of this project:
1. Please provide your solutions to the questions;
2. Please vote for the best solutions by pressing Kudos button;
3. Please vote for the questions themselves by pressing Kudos button;
4. Please share your views on difficulty level of the questions, so that we have most precise evaluation.

Thank you!

_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Expert Post
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 45222
Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 02 Jul 2012, 02:39
Expert's post
2
This post was
BOOKMARKED
Current Student
User avatar
B
Joined: 29 Mar 2012
Posts: 317
Location: India
GMAT 1: 640 Q50 V26
GMAT 2: 660 Q50 V28
GMAT 3: 730 Q50 V38
GMAT ToolKit User
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 02 Jul 2012, 02:44
Hi,

Difficulty level: 600

Using (1),
x = y + 2, so for any value of y, x > y. Sufficient.

Using (2),
x/2 = y - 1
for x = 0, y = 1 or x < y
for x = 2, y = 2 or x = y
for x = 4, y = 3 or x > y, Thus the relationship depends on value of x & y. Insufficient.

Thus, Answer is (A)

Regards,
Intern
Intern
avatar
Joined: 25 Apr 2012
Posts: 1
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 02 Jul 2012, 12:28
1) Sufficient . X is always 2 greater than Y. (+,-ve and fraction).
2) Insufficient. For y=5, x = 8 so x> y but for y=-5, x= -12 so y> x..

A)
Senior Manager
Senior Manager
User avatar
Joined: 23 Oct 2010
Posts: 364
Location: Azerbaijan
Concentration: Finance
Schools: HEC '15 (A)
GMAT 1: 690 Q47 V38
GMAT ToolKit User
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 03 Jul 2012, 09:53
(1) x = y+2 sufficient .try zero, negative, positive integers and non-integers, and u will get answer YES, x>y.
(2) x/2 = y-1 means x=2(y-1) if y=1 x =0 so, the answ is No, but if y=3 x=4 the answer is Yes
_________________

Happy are those who dream dreams and are ready to pay the price to make them come true

I am still on all gmat forums. msg me if you want to ask me smth

1 KUDOS received
Manager
Manager
avatar
Joined: 07 Sep 2011
Posts: 69
GMAT 1: 660 Q41 V40
GMAT 2: 720 Q49 V39
WE: Analyst (Mutual Funds and Brokerage)
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 03 Jul 2012, 13:42
1
This post received
KUDOS
Is x > y?

(1) x = y+2
Regardless of whether y is a positive or negative, if x=y+2, then y is greater than x. SUFFICIENT.
(2) x/2 = y-1
This kind of logic pops up frequently from the GMAT probelms I have done.
x=2(y-1)
x=2y-2
Whenever you see mult/div AND sub/add on the other side of x, you won't be able to tell whether whether one integer is greater than the other. It could be either of the case.

Answer: A
Expert Post
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 5423
GMAT 1: 800 Q59 V59
GPA: 3.82
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 21 Nov 2015, 10:18
Forget conventional ways of solving math questions. In DS, Variable approach is the easiest and quickest way to find the answer without actually solving the problem. Remember equal number of variables and independent equations ensures a solution.

Is x > y?

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

We get x-y>0? when we modify the questions.
For condition 1, x-y=2>0 This is a 'yes', and sufficient.
For condition 2, x=2y-2, x-y=y-2. We cannot determine the sign of x-y, so this is insufficient.
The answer (A).

For (C), x=y+2, x=2y-2 --> y=2, x=4. This is insufficient as it is too trivial.

Once we modify the original condition and the question according to the variable approach method 1, we can solve approximately 30% of DS questions.
_________________

MathRevolution: Finish GMAT Quant Section with 10 minutes to spare
The one-and-only World’s First Variable Approach for DS and IVY Approach for PS with ease, speed and accuracy.
"Only $79 for 3 month Online Course"
"Free Resources-30 day online access & Diagnostic Test"
"Unlimited Access to over 120 free video lessons - try it yourself"

Expert Post
EMPOWERgmat Instructor
User avatar
D
Status: GMAT Assassin/Co-Founder
Affiliations: EMPOWERgmat
Joined: 19 Dec 2014
Posts: 11647
Location: United States (CA)
GMAT 1: 800 Q51 V49
GRE 1: 340 Q170 V170
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 13 Dec 2017, 21:25
Hi All,

We're asked if X is greater than Y. This is a YES/NO question. We can solve it by TESTing VALUES.

1) X = Y +2

With this Fact, we can see that X is "2 greater" than Y, so the answer to the question is ALWAYS YES. You can see this pattern with a few TESTs:
IF....
Y = 0, X = 2
Y = 5, X = 7
Y = -3, X = -1
Etc.
Fact 1 is SUFFICIENT

2) X/2 = Y - 1

IF....
Y = 1, X = 0 and the answer to the question is NO
Y = 3, X = 4 and the answer to the question is YES
Fact 2 is INSUFFICIENT

Final Answer:

GMAT assassins aren't born, they're made,
Rich
_________________

760+: Learn What GMAT Assassins Do to Score at the Highest Levels
Contact Rich at: Rich.C@empowergmat.com

Rich Cohen

Co-Founder & GMAT Assassin

Special Offer: Save $75 + GMAT Club Tests Free
  Official GMAT Exam Packs + 70 Pt. Improvement Guarantee
www.empowergmat.com/

***********************Select EMPOWERgmat Courses now include ALL 6 Official GMAC CATs!***********************

Manager
Manager
avatar
B
Joined: 23 Oct 2017
Posts: 64
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 13 Dec 2017, 21:48
stmt 1: x= y +2 => x-y = 2 => x-y >0 => x > y (sufficient)
stmt 2: x/2 = y-1 => x = 2y -2 => x- 2y <0 => x< 2y (not sufficient)
Manager
Manager
avatar
G
Joined: 21 Jul 2015
Posts: 161
Reviews Badge
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 26 Jan 2018, 14:54
Bunuel VeritasPrepKarishma

Could you please provide graphical approach to solve Statement 2? I am able to draw the line on the graph. The line meets the x axis and y axis at points (-2,0) and (0,1) respectively. From this point, how do we determine if there would be a case when y < x. Number plugging approach doesn't come very easily to me, so trying out other ways to solve.

Thanks for your help!!
_________________

Please take a moment to hit Kudos if my post helps.

1 KUDOS received
DS Forum Moderator
avatar
G
Joined: 22 Aug 2013
Posts: 1141
Location: India
Premium Member CAT Tests
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 29 Jan 2018, 01:42
1
This post received
KUDOS
sdlife wrote:
Bunuel VeritasPrepKarishma

Could you please provide graphical approach to solve Statement 2? I am able to draw the line on the graph. The line meets the x axis and y axis at points (-2,0) and (0,1) respectively. From this point, how do we determine if there would be a case when y < x. Number plugging approach doesn't come very easily to me, so trying out other ways to solve.

Thanks for your help!!


Hi

They can provide better explanation but I will try. So you have drawn a line of x/2 = y - 1. The other line you should also draw is x = y (or y = x). Why you may ask? Because the question asks you whether x is > y or not? Once you have the line y = x on the graph (it will be a line with positive slope of 1 passing through origin inclined at 45 degrees with x axis), you can see that:- the area on graph below this line y=x will be the area where x > y and the area on the graph above this line y=x will be the area where x < y.

So on one hand, you have this line y=x and on the other hand you have the line x/2 = y-1. You will see that some part of line x/2 = y-1 will fall below the y=x line and some part of line x/2 = y-1 will be above the y=x line. So what does this tell us? This tells us that with the data x/2 = y-1, we CANNOT be sure whether x > y or not.
Expert Post
1 KUDOS received
Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8064
Location: Pune, India
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 30 Jan 2018, 03:00
1
This post received
KUDOS
Expert's post
sdlife wrote:
Bunuel VeritasPrepKarishma

Could you please provide graphical approach to solve Statement 2? I am able to draw the line on the graph. The line meets the x axis and y axis at points (-2,0) and (0,1) respectively. From this point, how do we determine if there would be a case when y < x. Number plugging approach doesn't come very easily to me, so trying out other ways to solve.

Thanks for your help!!


Yes, you have the line which depicts x/2 = y-1. You see that this represents a line with slope 1/2. So y increases by 1/2 for every 1 unit increase in x.
It passes through (-2, 0) and (0, 1). So if x increases by 2, y increases by 1 so (2, 2) lies on this line. If x increases by another 2, y increases just by 1 so (4, 3) lies on this line too.
In case of some points x > y and in other cases x < y. So this statement alone is not sufficient.
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for $199

Veritas Prep Reviews

Manager
Manager
avatar
G
Joined: 21 Jul 2015
Posts: 161
Reviews Badge
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 30 Jan 2018, 14:29
VeritasPrepKarishma wrote:

Yes, you have the line which depicts x/2 = y-1. You see that this represents a line with slope 1/2. So y increases by 1/2 for every 1 unit increase in x.
It passes through (-2, 0) and (0, 1). So if x increases by 2, y increases by 1 so (2, 2) lies on this line. If x increases by another 2, y increases just by 1 so (4, 3) lies on this line too.
In case of some points x > y and in other cases x < y. So this statement alone is not sufficient.


Hi Karishma,

Thank you very much for your response. Could you please explain the highlighted part?

SD
_________________

Please take a moment to hit Kudos if my post helps.

Manager
Manager
avatar
G
Joined: 21 Jul 2015
Posts: 161
Reviews Badge
Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 30 Jan 2018, 19:43
amanvermagmat wrote:
They can provide better explanation but I will try. So you have drawn a line of x/2 = y - 1. The other line you should also draw is x = y (or y = x). Why you may ask? Because the question asks you whether x is > y or not? Once you have the line y = x on the graph (it will be a line with positive slope of 1 passing through origin inclined at 45 degrees with x axis), you can see that:- the area on graph below this line y=x will be the area where x > y and the area on the graph above this line y=x will be the area where x y or not.


amanvermagmat

Thanks a ton for your response. I do understand the solution now. A couple questions if you don't mind answering:

1) How did you think of drawing a line x=y for this question? One clue maybe since it was asked if x>y? But I couldn't even think of it. Any tips on how to solve these type of problems?

2) Probably a dumb question. How do decide that the side above the line y=x will have y>x, while below is x<y?

Thank you very much for your help!
_________________

Please take a moment to hit Kudos if my post helps.

Expert Post
1 KUDOS received
Veritas Prep GMAT Instructor
User avatar
P
Joined: 16 Oct 2010
Posts: 8064
Location: Pune, India
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 30 Jan 2018, 21:57
1
This post received
KUDOS
Expert's post
sdlife wrote:
VeritasPrepKarishma wrote:

Yes, you have the line which depicts x/2 = y-1. You see that this represents a line with slope 1/2. So y increases by 1/2 for every 1 unit increase in x.
It passes through (-2, 0) and (0, 1). So if x increases by 2, y increases by 1 so (2, 2) lies on this line. If x increases by another 2, y increases just by 1 so (4, 3) lies on this line too.
In case of some points x > y and in other cases x < y. So this statement alone is not sufficient.


Hi Karishma,

Thank you very much for your response. Could you please explain the highlighted part?

SD


Check this post. It explains you the slope concept of the line.

http://www.veritasprep.com/blog/2010/12 ... he-graphs/
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for $199

Veritas Prep Reviews

1 KUDOS received
DS Forum Moderator
avatar
G
Joined: 22 Aug 2013
Posts: 1141
Location: India
Premium Member CAT Tests
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1 [#permalink]

Show Tags

New post 30 Jan 2018, 22:08
1
This post received
KUDOS
sdlife wrote:
amanvermagmat wrote:
They can provide better explanation but I will try. So you have drawn a line of x/2 = y - 1. The other line you should also draw is x = y (or y = x). Why you may ask? Because the question asks you whether x is > y or not? Once you have the line y = x on the graph (it will be a line with positive slope of 1 passing through origin inclined at 45 degrees with x axis), you can see that:- the area on graph below this line y=x will be the area where x > y and the area on the graph above this line y=x will be the area where x y or not.


amanvermagmat

Thanks a ton for your response. I do understand the solution now. A couple questions if you don't mind answering:

1) How did you think of drawing a line x=y for this question? One clue maybe since it was asked if x>y? But I couldn't even think of it. Any tips on how to solve these type of problems?

2) Probably a dumb question. How do decide that the side above the line y=x will have y>x, while below is x<y?

Thank you very much for your help!


Hi

I dont mind answering any questions, as far as I know their answers :)

1) Yes, you are right. I thought of drawing x=y because I got the clue from x > y (which the question was asking). As you understand more about graphs, I am sure you will get better in these.

2) Once you plot the line y=x, I am sure you would agree that on one side of it, x > y and on another side of it x < y. How to check which is which? Just take any one point from any one side of the line, and see whether it fits in x > y or x < y. Eg., here you have the line y=x with you. Now on the right side of this line (or below) lets choose a point (3,-1). The x-coordinate of the point is 3, and y coordinate is -1, and its clear that here x > y. So no need to check further, we can be sure that on the right side of the line x=y, all points will have x > y. This means automatically on the left side of the line (or you can say above the line), all points will have x < y (or you could check with any point above the line x=y, and you will find that x < y.
Re: Is x > y? (1) x= y+2 (2) x/2 = y-1   [#permalink] 30 Jan 2018, 22:08
Display posts from previous: Sort by

Is x > y? (1) x= y+2 (2) x/2 = y-1

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


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®.