GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 15 Aug 2018, 19:24

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

If the operation x&y is defined by the equation x&y=x·y/(x+y) for all

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

Hide Tags

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47920
If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 21 Mar 2017, 09:18
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

92% (00:40) correct 8% (01:21) wrong based on 78 sessions

HideShow timer Statistics

Moderator
avatar
V
Joined: 22 Jun 2014
Posts: 1059
Location: India
Concentration: General Management, Technology
GMAT 1: 540 Q45 V20
GPA: 2.49
WE: Information Technology (Computer Software)
GMAT ToolKit User Premium Member
Re: If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 21 Mar 2017, 11:13
Bunuel wrote:
If the operation x&y is defined by the equation x&y=x·y/(x+y) for all x≠−y, then (18)&(9)=

A. 2
B. 3
C. 6
D. 9
E. 12


(18)&(9) = 18*9/(18+9) = 18*9/27 = 6

Answer - C
_________________

---------------------------------------------------------------
Target - 720-740
http://gmatclub.com/forum/information-on-new-gmat-esr-report-beta-221111.html
http://gmatclub.com/forum/list-of-one-year-full-time-mba-programs-222103.html

Board of Directors
User avatar
P
Status: QA & VA Forum Moderator
Joined: 11 Jun 2011
Posts: 3757
Location: India
GPA: 3.5
WE: Business Development (Commercial Banking)
GMAT ToolKit User Premium Member
If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 21 Mar 2017, 11:23
Bunuel wrote:
If the operation x&y is defined by the equation x&y=x·y/(x+y) for all x≠−y, then (18)&(9)=

A. 2
B. 3
C. 6
D. 9
E. 12


\(x&y=x·y/(x+y)\)

Or, \(\frac{(18)&(9) = 18*9}{( 18 + 9 )}\)

Or, \((18)&(9) = \frac{162}{27}\)

Or, \((18)&(9) = 6\)

Thus, answer must be (C) 6
_________________

Thanks and Regards

Abhishek....

PLEASE FOLLOW THE RULES FOR POSTING IN QA AND VA FORUM AND USE SEARCH FUNCTION BEFORE POSTING NEW QUESTIONS

How to use Search Function in GMAT Club | Rules for Posting in QA forum | Writing Mathematical Formulas |Rules for Posting in VA forum | Request Expert's Reply ( VA Forum Only )

Senior Manager
Senior Manager
avatar
B
Joined: 06 Dec 2016
Posts: 251
Re: If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 21 Mar 2017, 15:49
This one is ridiculously easy.

18 x 9/18 +9
162/27
6

Answer is C
Manager
Manager
User avatar
S
Joined: 31 May 2015
Posts: 81
GMAT ToolKit User
Re: If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 23 Oct 2017, 01:09
Does anyone get why does statement mentions x≠−y.
_________________

GMAT loosers are born not made !!!

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 47920
Re: If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 23 Oct 2017, 01:17
Target Test Prep Representative
User avatar
G
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2727
Re: If the operation x&y is defined by the equation x&y=x·y/(x+y) for all  [#permalink]

Show Tags

New post 26 Oct 2017, 15:31
Bunuel wrote:
If the operation x&y is defined by the equation x&y=x·y/(x+y) for all x≠−y, then (18)&(9)=

A. 2
B. 3
C. 6
D. 9
E. 12


(18)&(9) = (18 * 9)/(9 + 18) = (18 * 9)/27 = (2 * 9)/3 = 2 * 3 = 6

Answer: C
_________________

Jeffery Miller
Head of GMAT Instruction

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

Re: If the operation x&y is defined by the equation x&y=x·y/(x+y) for all &nbs [#permalink] 26 Oct 2017, 15:31
Display posts from previous: Sort by

If the operation x&y is defined by the equation x&y=x·y/(x+y) for all

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

Events & Promotions

PREV
NEXT


GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| 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®.