NEW HERE? LEARN MORE
closeclose
Last visit was: 23 Apr 2024, 23:36 It is currently 23 Apr 2024, 23:36
Decision Tracker
My Rewards
New posts
New comers' posts

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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel

GRE Weekly Challenge #3

SORT BY:
Date
Kudos
User avatar
rasta
Retired Moderator
Joined: 25 Jul 2011
Posts: 299
Own Kudos [?]: 313 [1]
Given Kudos: 286
Location: India
Concentration: Strategy, General Management
Schools: Said'16 AGSM '16 INSEAD Jan '16 Imperial '18 ISB '17 LBS
GMAT 1: 730 Q50 V40
GRE 1: Q800 V800
GPA: 3
WE:Operations (Non-Profit and Government)
Send PM
GMAT ToolKit User
GRE Weekly Challenge #3 [#permalink] New post   14 Sep 2011, 21:57
1
Kudos
GMAT Club invites you to test your GRE knowledge for a chance to win! Each week, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that week’s drawing for a free Manhattan GRE Strategy guide. What are you waiting for? Get out their scrap paper and start solving! Click here to view contest & prize details


This week's question:



A
B
|x – 5| – |a – b||b – a| – |5 – x|


Compare Quantity A and Quantity B using the information given above, and select one of the following answer choices:
A) Quantity A is greater.
B) Quantity B is greater.
C) The two quantities are equal.
D) The relationship cannot be determined from the information given.


Please post your answer, along with the explanation, below. Get cracking! :)

Edit: This challenge is now closed


The winner of this Week's Challenge is... (drum roll).... m2l2. Congratulations! Please send me a pm with your shipping address, and choice of Manhattan GRE Guide


Details of next week's competition will be posted in the Weekly Challenge Master thread... Stay tuned!
User avatar
L
GyanOne
CEO
CEO
Joined: 24 Jul 2011
Status: World Rank #4 MBA Admissions Consultant
Posts: 3187
Own Kudos [?]: 1585 [0]
Given Kudos: 33
GMAT 1: 780 Q51 V48
GRE 1: Q170 V170
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   Updated on: 17 Sep 2011, 07:17
Expert Reply
Should be (B)

Originally posted by GyanOne on 14 Sep 2011, 23:13.
Last edited by GyanOne on 17 Sep 2011, 07:17, edited 1 time in total.
avatar
nvgroshar
Intern
Intern
Joined: 15 Nov 2009
Posts: 4
Own Kudos [?]: 15 [0]
Given Kudos: 0
Location: Moscow, Russia
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   15 Sep 2011, 08:45
Answer B. The difference between B-A= 2|b-a| -2|x-5|>,0 since |b-a|>5 and |x-5|<5.
In details, b>5, a<0, b-a>5; x<10; x-5<5.
avatar
AngelinaOllon
Intern
Intern
Joined: 12 Feb 2011
Posts: 2
Own Kudos [?]: 4 [0]
Given Kudos: 4
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   15 Sep 2011, 11:45
Answer B - Quantity B is greater.‎
‎|x – 5|=|5 – x|;‎
‎|a – b|=|b – a|;‎
As 5<x<10, then 0<|x – 5|<5 and 0<|5 – x|<5;‎
As a<0, b>0, then |a – b|=|b – a|=|a|+|b|;‎
‎|a|>0 and 5<|b|<10, then (|a|+|b|)>5;‎
Therefore, |x – 5| < |a – b|, (|x – 5| – |a – b|) < 0 and ‎
‎(|b – a| – |5 – x|) > 0, which means that‎
‎(|x – 5| – |a – b|) < (|b – a| – |5 – x|) for all a, b, x.‎
User avatar
m2l2
Intern
Intern
Joined: 13 May 2011
Status:single
Posts: 13
Own Kudos [?]: 38 [0]
Given Kudos: 6
Location: India
Concentration: Entrepreneurship, Strategy
GPA: 3
WE:Manufacturing and Production (Other)
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   15 Sep 2011, 13:13
Quantity B is greater.
A=|x-5|-|a-b|
= (x-5)-(-(a-b)

since x>5, so the mod will always open positive.
since a<b, |a-b| will always open negetive.

so A= x-5+a-b ............(i)

B=|b-a|-|5-x|
= (b-a)-(-(5-x)
same logic as above.

so B= b-a+5-x ...............(ii)

so A= -(B) ............... from (i) and (ii)
now,
numerical value of b-a is greater than 5 since 0 and 5 lies between a and b.
numerical value of 5-x is less than 5 since x lies between 5 and 10.
so, B is a positive quantity or A is a negetive quantity.

therefore, B>A
User avatar
dreambeliever
Manager
Manager
Joined: 24 Nov 2010
Posts: 119
Own Kudos [?]: 247 [0]
Given Kudos: 7
Location: United States (CA)
Concentration: Technology, Entrepreneurship
Schools: Duke '15 Ross '15
Send PM
GMAT ToolKit User
Re: GRE Weekly Challenge #3 [#permalink] New post   15 Sep 2011, 19:53
Ans B

Let |x-5| = |5-x| = c --> 0<c<5
Let |a - b| = |b - a| = d --> 5<d<infinity

A = |x – 5| – |a – b| = (0<c<5) - (5<d<infinity) = -ve
B = |b – a| – |5 – x| = (5<d<infinity) - (0<c<5) = +ve

therefore B is greater
avatar
ramvemula
Intern
Intern
Joined: 23 Aug 2011
Posts: 6
Own Kudos [?]: [0]
Given Kudos: 1
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   15 Sep 2011, 21:55
Ans: D

The intervals is not equal so we can not determine !!
Ardarandir
Joined: 31 Dec 1969
Own Kudos [?]: [0]
Given Kudos:
Concentration: Entrepreneurship, International Business
WE:Supply Chain Management (Energy and Utilities)
Re: GRE Weekly Challenge #3 [#permalink] New post   16 Sep 2011, 05:23
The correct answer is: B)Quantity B is greater.

Quantity A:

0 < |x-5| < 5

|a-b| > b ==> |a-b| > 5

==>
|x – 5| – |a – b| = (0 < |x-5| < 5) - (|a-b| > 5) <=== This expression is clearly smaller than 0

Quantity B:

|b – a| = b+|a| > 5

|5 – x| < 5 (since 5 < x < 10 )

==>
|b – a| – |5 – x| = ( b+|a| > 5) - (|5 – x| < 5) <=== This expression is clearly greater than 0

So quantity B is greater than quantity A.
avatar
arjungn
Intern
Intern
Joined: 19 Jun 2011
Posts: 3
Own Kudos [?]: [0]
Given Kudos: 0
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   16 Sep 2011, 10:49
Quantity B

|5-x|-->X varies from 5 to 10 therefore |5-x| varies from 0 to 5
|b-a|--> B varies from 5 to 10 and is greater then X ..and A is less than 0.Therefore |b-a| is either greater then 10 or greater than 5.Which means greater than 5 covers the entire range.
Hence ,|b-a|-|5-x| is always positive...(1)

Quantity A
Since x > 0 , |x-5| is the same range as |5-x| varying from 0 to 5
|a-b| again as |b-a| varies from 5 to 10
Hence . |b-a|-|5-x| is < 0 ....(2)

Therefore Clearly , Quantity B is greater then Quantity A.
avatar
viraa
Intern
Intern
Joined: 18 Sep 2011
Posts: 3
Own Kudos [?]: [0]
Given Kudos: 0
Send PM
Re: GRE Weekly Challenge #3 [#permalink] New post   22 Sep 2011, 22:45
ready to participage....
GMAT Club Bot
gmatclubot
Re: GRE Weekly Challenge #3 [#permalink]
22 Sep 2011, 22:45

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne
Main navigation
GMAT Resources
Partners
MBA Resources
www.gmac.com|www.mba.com | | GMAT Club Rules | Terms and Conditions