Is x the square of an integer? : GMAT Data Sufficiency (DS)
Check GMAT Club App Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

It is currently 09 Dec 2016, 19:38
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

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Is x the square of an integer?

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

Hide Tags

1 KUDOS received
Manager
Manager
avatar
Joined: 13 Dec 2009
Posts: 129
Followers: 6

Kudos [?]: 276 [1] , given: 10

Is x the square of an integer? [#permalink]

Show Tags

New post 24 Apr 2010, 21:25
1
This post received
KUDOS
1
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

58% (01:43) correct 42% (01:03) wrong based on 110 sessions

HideShow timer Statistics

Is x the square of an integer?

(1) x = 12k + 6, where k is a positive integer
(2) x = 3q + 9, where q is a positive integer

OPEN DISCUSSION OF THIS QUESTION IS HERE: is-x-the-square-of-an-integer-126385.html
[Reveal] Spoiler: OA

Last edited by Bunuel on 13 Nov 2013, 01:12, edited 1 time in total.
Edited the question and added the OA.
5 KUDOS received
Manager
Manager
avatar
Joined: 27 Dec 2009
Posts: 171
Followers: 2

Kudos [?]: 94 [5] , given: 3

Re: Is x the square of an integer [#permalink]

Show Tags

New post 24 Apr 2010, 23:30
5
This post received
KUDOS
From Stmt 1 ,
x= 6(2k+1) where k = positive integer.
2k + 1 is always odd.
To be a square of an integer, 2k+1 has to be a multiple of 6 and that is not possible.
So, x can't be square of an integer.

Stmt 1 sufficient.

From Stmt 2,
x= 3(q+3)
putting different values of q can have 2 different results.
Example put q=1, x =12 ... not a square of an integer
put q=24 , x = 81 ... square of an integer 9.

Stmt 2 ,Not sufficient.

Answer : A
Director
Director
User avatar
Status: Verbal Forum Moderator
Joined: 17 Apr 2013
Posts: 635
Location: India
GMAT 1: 710 Q50 V36
GMAT 2: 750 Q51 V41
GMAT 3: 790 Q51 V49
GPA: 3.3
Followers: 63

Kudos [?]: 411 [0], given: 297

Re: Is x the square of an integer? (1) x = 12k+6 , where k is a [#permalink]

Show Tags

New post 13 Nov 2013, 00:38
Bunuel is their some expert easy way to solve it?
_________________

Like my post Send me a Kudos :) It is a Good manner.
My Debrief: http://gmatclub.com/forum/how-to-score-750-and-750-i-moved-from-710-to-189016.html

Expert Post
2 KUDOS received
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 35932
Followers: 6860

Kudos [?]: 90101 [2] , given: 10413

Re: Is x the square of an integer? [#permalink]

Show Tags

New post 13 Nov 2013, 01:13
2
This post received
KUDOS
Expert's post
Is x the square of an integer?

(1) x = 12k + 6, where k is a positive integer --> \(x=6(2k+1)=2*3(2k+1)\). Now, \(x\) to be a perfect square it should have an even power of its primes, but \(2k+1\) is an odd number and can no way produce 2 for \(x\). Thus \(x\) is not a perfect square. Sufficient.

(2) x = 3q + 9, where q is a positive integer --> \(x=3(q+3)\). If \(q=1\) then \(x=12\) and the answer is NO but if \(q=9\) then \(x=36\) and the answer is YES (basically if (q+3)=3*any perfect square then x will be a perfect square and if (q+3) is some other type of number then x won't be a perfect square). Not sufficient.

Answer: A.

OPEN DISCUSSION OF THIS QUESTION IS HERE: is-x-the-square-of-an-integer-126385.html
_________________

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

Re: Is x the square of an integer?   [#permalink] 13 Nov 2013, 01:13
    Similar topics Author Replies Last post
Similar
Topics:
Is a positive integer x square of an integer? stonecold 1 22 Nov 2016, 21:58
3 Experts publish their posts in the topic Is the square root of x is an integer? sanjoo 7 07 Mar 2014, 04:54
1 Experts publish their posts in the topic Is the positive square root of x an integer? blackcrow 2 29 Dec 2013, 01:13
10 Experts publish their posts in the topic Is x the square of an Integer? enigma123 5 21 Jan 2012, 13:56
2 Experts publish their posts in the topic Is the positive square root of x an integer? metallicafan 2 28 Nov 2011, 09:31
Display posts from previous: Sort by

Is x the square of an integer?

  post reply Question banks Downloads My Bookmarks Reviews Important topics  


cron

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®.