Find all School-related info fast with the new School-Specific MBA Forum

It is currently 30 Aug 2014, 14:53

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

ds question

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 11 Sep 2006
Posts: 41
Followers: 0

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

ds question [#permalink] New post 05 Oct 2006, 13:08
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Is n an integer?
(1) n^2 is an integer
(2) n^1/2 is an integer.

My answer is D that they are each sufficient. My logic is that if n squared is an integer, then n has to be an integer. When is there an instance that n squared is an integer but n isnt.


The answer guide says B.

Can someone explain this to me.
SVP
SVP
User avatar
Joined: 01 May 2006
Posts: 1816
Followers: 8

Kudos [?]: 88 [0], given: 0

GMAT Tests User
 [#permalink] New post 05 Oct 2006, 13:12
Pick numbers ;)

Stat 1 :
o n^2 = 4 > n = 2 or n = -2
o n^2 = 5 > n = sqrt(5) or n = -sqrt(5)

INSUFF

Stat 2 :
sqrt(n) = k (k an integer)
<=> n = k^2 = k*k
Thus, n is an integer

SUFF
SVP
SVP
User avatar
Joined: 05 Jul 2006
Posts: 1542
Followers: 5

Kudos [?]: 71 [0], given: 39

 [#permalink] New post 05 Oct 2006, 13:25
Is n an integer?
(1) n^2 is an integer
(2) n^1/2 is an integer.

ONE

N COULD BE SQRT OF AN INTIGER..........NOT SUFF

FROM TWO

SQRT N IS INTIGER THUS SURE N IS INTIGER..SUFF

MY ANSWER IS B
Director
Director
avatar
Joined: 06 Sep 2006
Posts: 746
Followers: 1

Kudos [?]: 15 [0], given: 0

GMAT Tests User
 [#permalink] New post 05 Oct 2006, 13:55
Is n an integer?
(1) n^2 is an integer
(2) n^1/2 is an integer.

1) arbitrary values for n^2=0,1,2,3,4,.. so we can't sat if n is an integer INSUFF.

2) n^1/2 = 1, 2, 3, 4, 5
picking any and squaring both sides will leave us with an integer.
SUFFICIENT

B.
Senior Manager
Senior Manager
User avatar
Joined: 30 Aug 2006
Posts: 374
Followers: 2

Kudos [?]: 7 [0], given: 0

GMAT Tests User
 [#permalink] New post 05 Oct 2006, 15:15
B

n could be sqrt(2) or sqrt(3) or sqrt(7) etc.

sqrt(7) * sqrt(7) = 7, but sqrt(7) is not an integer.
  [#permalink] 05 Oct 2006, 15:15
    Similar topics Author Replies Last post
Similar
Topics:
DS Question vijay2001 1 15 Apr 2007, 18:37
DS question gmatornot 4 13 Sep 2006, 20:48
DS Question lan583 1 04 Aug 2006, 13:09
DS question microjohn 16 03 Aug 2006, 17:43
1 DS question lealexandre 2 08 Dec 2005, 00:25
Display posts from previous: Sort by

ds question

  Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| Privacy Policy| 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®.