If y is an integer and y=|x|+x, is y=0? : GMAT Data Sufficiency (DS)
Check GMAT Club Decision Tracker for the Latest School Decision Releases https://gmatclub.com/AppTrack

It is currently 21 Feb 2017, 22:45
GMAT Club Tests

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

If y is an integer and y=|x|+x, is y=0?

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

Hide Tags

2 KUDOS received
Manager
Manager
avatar
Joined: 10 Sep 2010
Posts: 133
Followers: 2

Kudos [?]: 33 [2] , given: 7

If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 14 Dec 2010, 21:03
2
This post received
KUDOS
2
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

52% (01:59) correct 48% (00:53) wrong based on 191 sessions

HideShow timer Statistics

If y is an integer and y=|x|+x, is y=0?

(1) x<0
(2) y<1
[Reveal] Spoiler: OA
1 KUDOS received
Director
Director
User avatar
Joined: 03 Sep 2006
Posts: 879
Followers: 6

Kudos [?]: 796 [1] , given: 33

GMAT ToolKit User
Re: tricky q from GMATPrep2 [#permalink]

Show Tags

New post 14 Dec 2010, 21:39
1
This post received
KUDOS
Each of (1) and (2) are sufficient to answer the question. Thus the answer should be "D".
From(1), any value of X<0, whether it's integer or fraction will lead to Y = 0 because the mode function will result in positive value and positive value added to same negative value will result in Zero.
From (2), We can have Y as negative Integer ( -1,-2....) if and only if the Right hand side of equation is different. It's just adding the same X and it can't lead to the negative value.

Yes it can definitely lead to the Zero.

Thus Answer should be D.

You can plug and play certain values ( numbers ) in order to verify the above.
Manager
Manager
avatar
Joined: 10 Sep 2010
Posts: 133
Followers: 2

Kudos [?]: 33 [0], given: 7

Re: tricky q from GMATPrep2 [#permalink]

Show Tags

New post 14 Dec 2010, 22:07
I got it. thanks
I just forgot that "y" is an integer. For some reason I thought that "y" can be 0<y<1.
Thanks. I need to be more careful.
Expert Post
1 KUDOS received
Math Expert
User avatar
G
Joined: 02 Sep 2009
Posts: 37063
Followers: 7241

Kudos [?]: 96265 [1] , given: 10729

Re: tricky q from GMATPrep2 [#permalink]

Show Tags

New post 15 Dec 2010, 00:50
1
This post received
KUDOS
Expert's post
Fijisurf wrote:
I am sure it is posted somewhere on the forum already , I just can't find it.


If y is an integer and y=|x|+x, is y=0?

(1)x<0
(2)y<1


If y is an integer and y = |x| + x, is y = 0?
(1) x < 0
(2) y < 1

Note: as \(y=|x|+x\) then \(y\) is never negative. If \(x>{0}\) then \(y=x+x=2x>0\) and if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\).

(1) \(x<0\) --> \(y=|x|+x=-x+x=0\). Sufficient.

(2) \(y<1\), as we concluded y is never negative, and we are given that \(y\) is an integer, hence \(y=0\). Sufficient.

Answer: D.

Also discussed in Inequality and absolute value questions from my collection: inequality-and-absolute-value-questions-from-my-collection-86939.html

Hope it's clear.
_________________

New to the Math Forum?
Please read this: 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

Senior Manager
Senior Manager
User avatar
Status: Bring the Rain
Joined: 17 Aug 2010
Posts: 406
Location: United States (MD)
Concentration: Strategy, Marketing
Schools: Michigan (Ross) - Class of 2014
GMAT 1: 730 Q49 V39
GPA: 3.13
WE: Corporate Finance (Aerospace and Defense)
Followers: 7

Kudos [?]: 45 [0], given: 46

Re: tricky q from GMATPrep2 [#permalink]

Show Tags

New post 15 Dec 2010, 06:33
I orginially had this as A, because I didn't read the question thoroughly to see y was an integer.

just goes to show how easy it is to miss something if you are going too fast.
_________________

Go Blue!

GMAT Club Premium Membership - big benefits and savings

Joined: 31 Dec 1969
Location: Russian Federation
Concentration: Technology, Entrepreneurship
GMAT 1: 710 Q49 V0
GMAT 2: 700 Q V
GMAT 3: 740 Q40 V50
GMAT 4: 700 Q48 V38
GMAT 5: 710 Q45 V41
GMAT 6: 680 Q47 V36
GMAT 7: Q42 V44
GMAT 8: Q42 V44
GMAT 9: 740 Q49 V42
GMAT 10: 740 Q V
GMAT 11: 500 Q47 V33
GMAT 12: 670 Q V
GMAT 13: 680 Q V
WE: Supply Chain Management (Energy and Utilities)
Followers: 0

Kudos [?]: 208 [0], given: 103089

Re: tricky q from GMATPrep2 [#permalink]

Show Tags

New post 16 Dec 2010, 00:33
tfincham86 wrote:
I orginially had this as A, because I didn't read the question thoroughly to see y was an integer.

just goes to show how easy it is to miss something if you are going too fast.

Same mistake... It kills me !!!!!!!!! :beat
Expert Post
Veritas Prep GMAT Instructor
User avatar
B
Joined: 16 Oct 2010
Posts: 7179
Location: Pune, India
Followers: 2163

Kudos [?]: 14004 [0], given: 222

Re: tricky q from GMATPrep2 [#permalink]

Show Tags

New post 16 Dec 2010, 05:51
Fijisurf wrote:
I am sure it is posted somewhere on the forum already , I just can't find it.


If y is an integer and y=|x|+x, is y=0?

(1)x<0
(2)y<1


A word of caution: When you read "If y is an integer and y=|x|+x", analyze it there and then. y can be a positive integer when x is positive, y will be 0 when x is negative and y will be 0 when x is 0."
Another important point to note here: When the author puts in extra effort to write "y is an integer" rather than "x and y are integers" , take special note that x may not be an integer. Not that it matters very much here but in many questions such a statement will have special significance.
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for $199

Veritas Prep Reviews

Intern
Intern
avatar
Joined: 19 Sep 2010
Posts: 15
Followers: 0

Kudos [?]: 30 [0], given: 4

please explain, why not D why only B [#permalink]

Show Tags

New post 25 Feb 2011, 07:26
Q19:
If y is an integer and y = !x! + x, is y = 0?
(1) x < 0
(2) y < 1
Expert Post
Math Expert
User avatar
G
Joined: 02 Sep 2009
Posts: 37063
Followers: 7241

Kudos [?]: 96265 [0], given: 10729

Re: please explain, why not D why only B [#permalink]

Show Tags

New post 25 Feb 2011, 08:02
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 13904
Followers: 589

Kudos [?]: 167 [0], given: 0

Premium Member
Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 06 Feb 2014, 03:45
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Intern
Intern
avatar
Joined: 01 Aug 2006
Posts: 35
Followers: 0

Kudos [?]: 29 [0], given: 0

Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 07 Feb 2014, 16:23
If y is an integer and y = |x| + x, is y = 0?
y = 0, when x < 0; y = 2x, when x >=0
(1) x < 0 => y = 0
(2) y < 1 -> Because y is an integer, y has to be zero (y cannot be a negative integer because the least value of y is zero).

D
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 13904
Followers: 589

Kudos [?]: 167 [0], given: 0

Premium Member
Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 30 Jun 2016, 02:23
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Intern
Intern
avatar
Joined: 23 Sep 2015
Posts: 47
Followers: 0

Kudos [?]: 3 [0], given: 98

Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 02:35
Bunuel wrote:
Fijisurf wrote:
I am sure it is posted somewhere on the forum already , I just can't find it.


If y is an integer and y=|x|+x, is y=0?

(1)x<0
(2)y<1


If y is an integer and y = |x| + x, is y = 0?
(1) x < 0
(2) y < 1

Note: as \(y=|x|+x\) then \(y\) is never negative. If \(x>{0}\) then \(y=x+x=2x>0\) and if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\).

please help!
(1) \(x<0\) --> \(y=|x|+x=-x+x=0\). Sufficient.

(2) \(y<1\), as we concluded y is never negative, and we are given that \(y\) is an integer, hence \(y=0\). Sufficient.

Answer: D.

Also discussed in Inequality and absolute value questions from my collection: inequality-and-absolute-value-questions-from-my-collection-86939.html

Hope it's clear.



the only place i'm stuck is
if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\)

if x is negative why arent we taking the other x as negative:\(y=-x-x=-2x\)
Expert Post
Math Expert
User avatar
G
Joined: 02 Sep 2009
Posts: 37063
Followers: 7241

Kudos [?]: 96265 [0], given: 10729

Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 02:48
nishantdoshi wrote:
Bunuel wrote:
Fijisurf wrote:
I am sure it is posted somewhere on the forum already , I just can't find it.


If y is an integer and y=|x|+x, is y=0?

(1)x<0
(2)y<1


If y is an integer and y = |x| + x, is y = 0?
(1) x < 0
(2) y < 1

Note: as \(y=|x|+x\) then \(y\) is never negative. If \(x>{0}\) then \(y=x+x=2x>0\) and if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\).

please help!
(1) \(x<0\) --> \(y=|x|+x=-x+x=0\). Sufficient.

(2) \(y<1\), as we concluded y is never negative, and we are given that \(y\) is an integer, hence \(y=0\). Sufficient.

Answer: D.

Also discussed in Inequality and absolute value questions from my collection: inequality-and-absolute-value-questions-from-my-collection-86939.html

Hope it's clear.



the only place i'm stuck is
if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\)

if x is negative why arent we taking the other x as negative:\(y=-x-x=-2x\)


Knowing that x is a negative number does not mean that you should replace it with -x, this just does not make any sense.
_________________

New to the Math Forum?
Please read this: 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

BSchool Forum Moderator
avatar
B
Joined: 18 Jul 2015
Posts: 1022
Location: India
Concentration: General Management, International Business
GMAT 1: 670 Q50 V32
GMAT 2: 700 Q50 V34
GPA: 3.65
WE: Brand Management (Health Care)
Followers: 25

Kudos [?]: 249 [0], given: 39

Premium Member Reviews Badge CAT Tests
Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 03:00
nishantdoshi wrote:
Bunuel wrote:
Fijisurf wrote:
I am sure it is posted somewhere on the forum already , I just can't find it.


If y is an integer and y=|x|+x, is y=0?

(1)x<0
(2)y<1


If y is an integer and y = |x| + x, is y = 0?
(1) x < 0
(2) y < 1

Note: as \(y=|x|+x\) then \(y\) is never negative. If \(x>{0}\) then \(y=x+x=2x>0\) and if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\).

please help!
(1) \(x<0\) --> \(y=|x|+x=-x+x=0\). Sufficient.

(2) \(y<1\), as we concluded y is never negative, and we are given that \(y\) is an integer, hence \(y=0\). Sufficient.

Answer: D.

Also discussed in Inequality and absolute value questions from my collection: inequality-and-absolute-value-questions-from-my-collection-86939.html

Hope it's clear.



the only place i'm stuck is
if \(x\leq{0}\) (when x is negative or zero) then \(y=-x+x=0\)

if x is negative why arent we taking the other x as negative:\(y=-x-x=-2x\)


No, you are missing something here.

We are given y = |x| + x, take the value of x as -2 and see the result.

Note that |x| is always positive,

When we say |x| = -x, we mean x will hold a negative value which when multiplied by -ve sign before will give a positive result. NEVER EVER take the values of mod like the way you have taken. I would suggest go through the mod concepts again.
_________________

Thanks.

Wanna say Thank you? Just hit Kudos. :-D

Intern
Intern
avatar
Joined: 23 Sep 2015
Posts: 47
Followers: 0

Kudos [?]: 3 [0], given: 98

Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 03:42
hey t hanks for the reply

When we say |x| = -x, we mean x will hold a negative value which when multiplied by -ve sign before will give a positive result. NEVER EVER take the values of mod like the way you have taken. I would suggest go through the mod concepts again.

i couldnt understand the above sentence

but my point is when we take x as -2,we get, y=|-2|-2 => y=-2-2 just like we do in the "Critical Points method" (if we get -ve value inside the mod we mult. the mod with the -ve sign.)

please give me detailed explanation if i'm wrong.please.
BSchool Forum Moderator
avatar
B
Joined: 18 Jul 2015
Posts: 1022
Location: India
Concentration: General Management, International Business
GMAT 1: 670 Q50 V32
GMAT 2: 700 Q50 V34
GPA: 3.65
WE: Brand Management (Health Care)
Followers: 25

Kudos [?]: 249 [0], given: 39

Premium Member Reviews Badge CAT Tests
If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 03:51
nishantdoshi wrote:
hey t hanks for the reply

When we say |x| = -x, we mean x will hold a negative value which when multiplied by -ve sign before will give a positive result. NEVER EVER take the values of mod like the way you have taken. I would suggest go through the mod concepts again.

i couldnt understand the above sentence

but my point is when we take x as -2,we get, y=|-2|-2 => y=-2-2 just like we do in the "Critical Points method" (if we get -ve value inside the mod we mult. the mod with the -ve sign.)

please give me detailed explanation if i'm wrong.please.


No Dude, your reasoning is 100% incorrect. As I said above |x| is always positive, so |-2| is always 2. Note that MOD means MAGNITUTE irrespective of sign.

Now, I can confidently say you are not aware of Mod concept used in mathematics.

Please go through the below link and try solving as many questions as you could.

http://magoosh.com/gmat/2012/gmat-math- ... te-values/
_________________

Thanks.

Wanna say Thank you? Just hit Kudos. :-D

1 KUDOS received
Intern
Intern
avatar
Joined: 23 Sep 2015
Posts: 47
Followers: 0

Kudos [?]: 3 [1] , given: 98

Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 04:00
1
This post received
KUDOS
abhimahna wrote:
nishantdoshi wrote:
hey t hanks for the reply

When we say |x| = -x, we mean x will hold a negative value which when multiplied by -ve sign before will give a positive result. NEVER EVER take the values of mod like the way you have taken. I would suggest go through the mod concepts again.

i couldnt understand the above sentence

but my point is when we take x as -2,we get, y=|-2|-2 => y=-2-2 just like we do in the "Critical Points method" (if we get -ve value inside the mod we mult. the mod with the -ve sign.)

please give me detailed explanation if i'm wrong.please.


No Dude, your reasoning is 100% incorrect. As I said above |x| is always positive, so |-2| is always 2. Note that MOD means MAGNITUTE irrespective of sign.

Now, I can confidently say you are not aware of Mod concept used in mathematics.

Please go through the below link and try solving as many questions as you could.

http://magoosh.com/gmat/2012/gmat-math- ... te-values/


thanks a lot. and can i pm you for doubts in other topics?
Intern
Intern
avatar
Joined: 03 Oct 2016
Posts: 3
Followers: 0

Kudos [?]: 6 [0], given: 1

Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 08 Oct 2016, 04:16
Break into 2 cases
a) x>0
then
y = 2x,
and y >=1 as y is an integer

b) x<= 0
then
y = 0

therefore
1) is sufficient as for x <0, y is 0
2) is sufficient as only possible value of y <1 is 0, coming from the case b).

Hence, an is D
SVP
SVP
User avatar
S
Joined: 17 Jul 2014
Posts: 2325
Location: United States (IL)
Concentration: Finance, Economics
Schools: Stanford '19 (S)
GMAT 1: 560 Q42 V26
GMAT 2: 550 Q39 V27
GMAT 3: 560 Q43 V24
GMAT 4: 650 Q49 V30
GPA: 3.92
WE: General Management (Transportation)
Followers: 23

Kudos [?]: 270 [0], given: 145

GMAT ToolKit User Premium Member Reviews Badge CAT Tests
Re: If y is an integer and y=|x|+x, is y=0? [#permalink]

Show Tags

New post 10 Nov 2016, 15:38
Fijisurf wrote:
If y is an integer and y=|x|+x, is y=0?

(1) x<0
(2) y<1



haha, what a classic trap!
i knew it when i saw 50% correct rate...
1. sufficient. x is negative, therefore y=0
2. y<1. sufficient. y must be zero. y can't be a decimal, since we are given the fact that y is an integer.

answer is D.
Re: If y is an integer and y=|x|+x, is y=0?   [#permalink] 10 Nov 2016, 15:38
    Similar topics Author Replies Last post
Similar
Topics:
Experts publish their posts in the topic If y is an integer, is y = 0? (1) When y is divided by an even intege Bunuel 1 12 Dec 2016, 11:50
2 Experts publish their posts in the topic Does x + y = 0? Bunuel 4 11 Dec 2014, 06:05
4 Experts publish their posts in the topic If n is a positive integer and y ≠ 0, what is the value of mvictor 6 07 Oct 2014, 13:51
11 Experts publish their posts in the topic Is |x| + |y| = 0? Warlock007 18 01 May 2011, 09:37
20 Experts publish their posts in the topic If y is an integer and y = |x| + x, is y = 0? devinawilliam83 8 21 Feb 2012, 21:07
Display posts from previous: Sort by

If y is an integer and y=|x|+x, is y=0?

  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 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®.