It is currently 19 Apr 2018, 14:18

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

|x-y|=? 1) x and y are different integers

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

Hide Tags

Expert Post
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 5245
GMAT 1: 800 Q59 V59
GPA: 3.82
|x-y|=? 1) x and y are different integers [#permalink]

Show Tags

New post 07 Dec 2017, 01:00
Expert's post
3
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  25% (medium)

Question Stats:

63% (00:46) correct 37% (00:30) wrong based on 108 sessions

HideShow timer Statistics

[GMAT math practice question]

\(|x-y|=?\)

1) \(x\) and \(y\) are different integers
2) \(xy=4\)
[Reveal] Spoiler: OA

_________________

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"

DS Forum Moderator
avatar
G
Joined: 22 Aug 2013
Posts: 1015
Location: India
Premium Member CAT Tests
Re: |x-y|=? 1) x and y are different integers [#permalink]

Show Tags

New post 07 Dec 2017, 01:56
2
This post was
BOOKMARKED
MathRevolution wrote:
[GMAT math practice question]

\(|x-y|=?\)

1) \(x\) and \(y\) are different integers
2) \(xy=4\)


(1) x and y are different integers. This just tells us that since they are not same, |x-y| cannot be 0. But there are so many possibilities. Insufficient.

(2) xy =4. So many possibilities. Eg, x=y=2, then |x-y| = 0, But if x=4, y=1 then |x-y| = 3. Insufficient.

Combining the two statements, x & y are different integers and their product =4. Lets look at the possibilities.
x=4, y=1
x=1, y=4
x=-4, y=-1
x=-1, y=-4

For each of the above cases, |x-y| = 3. So Sufficient. Hence C answer
Expert Post
Math Revolution GMAT Instructor
User avatar
D
Joined: 16 Aug 2015
Posts: 5245
GMAT 1: 800 Q59 V59
GPA: 3.82
Re: |x-y|=? 1) x and y are different integers [#permalink]

Show Tags

New post 10 Dec 2017, 18:07
=>

Forget conventional ways of solving math questions. For DS problems, the VA (Variable Approach) method is the quickest and easiest way to find the answer without actually solving the problem. Remember that equal numbers of variables and independent equations ensure a solution.

Since we have 2 variables (\(x\) and \(y\)) and 0 equations, C is most likely to be the answer. So, we should consider conditions 1) & 2) together first.

Condition 1) & 2)
Since x and y are different integers, \(xy = 4\) has the following four solutions:
\(x = 1, y = 4\)
\(x = 4, y = 1\)
\(x = -1, y = -4\)
\(x = -4, y = -1\)
In all cases, \(|x-y| = 3\).
Thus, both conditions 1) and 2) together are sufficient.

Therefore, C is the answer.

In cases where 3 or more additional equations are required, such as for original conditions with “3 variables”, or “4 variables and 1 equation”, or “5 variables and 2 equations”, conditions 1) and 2) usually supply only one additional equation. Therefore, there is an 80% chance that E is the answer, a 15% chance that C is the answer, and a 5% chance that the answer is A, B or D. Since E (i.e. conditions 1) & 2) are NOT sufficient, when taken together) is most likely to be the answer, it is generally most efficient to begin by checking the sufficiency of conditions 1) and 2), when taken together. Obviously, there may be occasions on which the answer is A, B, C or D.

Answer: C
_________________

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"

Intern
Intern
User avatar
B
Status: Studying Quant
Joined: 04 Sep 2017
Posts: 23
GPA: 3.6
WE: Sales (Computer Software)
Re: |x-y|=? 1) x and y are different integers [#permalink]

Show Tags

New post 13 Mar 2018, 03:53
Are -2, and 2 not "different integers"?
Board of Directors
User avatar
V
Status: Stepping into my 10 years long dream
Joined: 18 Jul 2015
Posts: 3341
Premium Member Reviews Badge CAT Tests
Re: |x-y|=? 1) x and y are different integers [#permalink]

Show Tags

New post 13 Mar 2018, 03:57
msurls wrote:
Are -2, and 2 not "different integers"?


Yes, they are. One is known as positive integer and the other positive integer. :)
_________________

How I improved from V21 to V40! ?


How to use this forum in THE BEST way?


New --> How ApplicantLab made me reach my 10 years long MBA dream?

DS Forum Moderator
avatar
G
Joined: 22 Aug 2013
Posts: 1015
Location: India
Premium Member CAT Tests
Re: |x-y|=? 1) x and y are different integers [#permalink]

Show Tags

New post 13 Mar 2018, 04:53
msurls wrote:
Are -2, and 2 not "different integers"?


Hello

Yes they are But their product is Not 4. As per second statement product should be 4
Re: |x-y|=? 1) x and y are different integers   [#permalink] 13 Mar 2018, 04:53
Display posts from previous: Sort by

|x-y|=? 1) x and y are different integers

  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®.