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

It is currently 19 Dec 2018, 05:44

TODAY:

MIT Sloan R1 Decisions - Join MIT Chat for Live Updates | Chat with UCLA Anderson Adcom @9am PT | Chat with Yale SOM R1 Admit 10am PT


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 in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • Happy Christmas 20% Sale! Math Revolution All-In-One Products!

     December 20, 2018

     December 20, 2018

     10:00 PM PST

     11:00 PM PST

    This is the most inexpensive and attractive price in the market. Get the course now!
  • Key Strategies to Master GMAT SC

     December 22, 2018

     December 22, 2018

     07:00 AM PST

     09:00 AM PST

    Attend this webinar to learn how to leverage Meaning and Logic to solve the most challenging Sentence Correction Questions.

Is (a − 5)^2 < (b + 5)^2 ?

  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: 51307
Is (a − 5)^2 < (b + 5)^2 ?  [#permalink]

Show Tags

New post 24 Apr 2017, 03:27
00:00
A
B
C
D
E

Difficulty:

  95% (hard)

Question Stats:

47% (02:22) correct 53% (02:14) wrong based on 159 sessions

HideShow timer Statistics

Senior PS Moderator
User avatar
V
Joined: 26 Feb 2016
Posts: 3327
Location: India
GPA: 3.12
Premium Member CAT Tests
Re: Is (a − 5)^2 < (b + 5)^2 ?  [#permalink]

Show Tags

New post 24 Apr 2017, 05:14
1
Is (a − 5)^2 < (b + 5)^2 ?
Using trial and error method.
(1) a < b
Lets consider the value a=0,b=1. These values, satisfy the condition
But if we take a=-2,b=-1, the condition does not hold.
Hence, not sufficient.

(2) a + b > 5
Lets consider a=4,b=2, the condition holds good.
However, if a = 15,b = -2, the condition doesn't hold good.
Hence, not sufficient.

On combining both, since one of the number definitely has to be positive,
we can mark the solution sufficient(Option C)
_________________

You've got what it takes, but it will take everything you've got

Intern
Intern
avatar
B
Joined: 25 Aug 2007
Posts: 38
GMAT ToolKit User Premium Member
Re: Is (a − 5)^2 < (b + 5)^2 ?  [#permalink]

Show Tags

New post 03 Sep 2017, 09:59
Official answer:
Attachments

GMAT1.JPG
GMAT1.JPG [ 131.49 KiB | Viewed 1218 times ]

PS Forum Moderator
avatar
D
Joined: 25 Feb 2013
Posts: 1217
Location: India
GPA: 3.82
GMAT ToolKit User Premium Member Reviews Badge
Is (a − 5)^2 < (b + 5)^2 ?  [#permalink]

Show Tags

New post 03 Sep 2017, 10:48
2
Bunuel wrote:
Is (a − 5)^2 < (b + 5)^2 ?

(1) a < b
(2) a + b > 5


Simplifying the question stem:
\((a-5)^2-(b+5)^2<0\) or \((a-5+b+5)(a-5-b-5)<0\) or \((a+b)(a-b-10)<0\).
Hence the question becomes IS \(a+b<0\) & \((a-b-10)>0\) or \((a+b)>0\) & \((a-b-10)<0\)

Statement 1: \(a<b\) or \(a-b<0\) so we can say that \(a-b-10<0\) (as it is summation of two negative terms)
but we know nothing about \(a\) & \(b\) so whether \(a+b<0\) or \(a+b>0\) can't be arrived at. For example if \(a=-3\) & \(b=-1\), then \(a+b<0\) as well as \(a-b<0\) but if \(a=1, b=2\), then \(a+b>0\) but \(a-b<0\). Hence the statement is not sufficient.

Statement 2: this implies that \(a+b>0\) but we know nothing about \((a-b)\), hence can't say that whether \(a-b-10<0\) or \(a-b-10>0\). For ex. if \(a=-1, b=7\) then \(a-b-10<0\) but if \(a=-1, b=13\) then \(a-b-10>0\). Hence insufficient

Combining 1 & 2
we know that \(a-b<0\), hence \(a-b-10<0\) and \(a+b>5\) hence \(a+b>0\). therefore \((a+b)(a-b-10)<0\). Hence sufficient

Option C
Director
Director
User avatar
D
Joined: 27 May 2012
Posts: 639
Premium Member
Re: Is (a − 5)^2 < (b + 5)^2 ?  [#permalink]

Show Tags

New post 21 Jul 2018, 09:31
Bunuel wrote:
Is (a − 5)^2 < (b + 5)^2 ?

(1) a < b
(2) a + b > 5


Dear Moderator ,
DS Question posted in PS forum, hope you will do the needful. Thank you.
_________________

- Stne

Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 51307
Re: Is (a − 5)^2 < (b + 5)^2 ?  [#permalink]

Show Tags

New post 21 Jul 2018, 11:07
GMAT Club Bot
Re: Is (a − 5)^2 < (b + 5)^2 ? &nbs [#permalink] 21 Jul 2018, 11:07
Display posts from previous: Sort by

Is (a − 5)^2 < (b + 5)^2 ?

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


Copyright

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®.