Welcome to Beat The GMAT, the world's largest GMAT & MBA forum. Please join our rich community of friendly members. Get free help from
experts who teach at the leading GMAT & MBA prep companies — Kaplan, Veritas Prep, Manhattan GMAT and Stacy Blackman Consulting.

Announcement: Apply for the Fall 2008 Beat The GMAT Scholarship, featuring $20,000 in prizes.

500 ds test4#17


 
Post new topic   Reply to topic    Beat The GMAT Forum Index -> GMAT Math -> Data Sufficiency
View previous topic :: View next topic  
Author Message
dunkin77
Really wants to Beat The GMAT!


Joined: 01 Apr 2007
Posts: 269

Thanks given: 0
Thanked 0 times in 0 posts
PostPosted: Thu Apr 05, 2007 5:38 pm    Post subject: 500 ds test4#17 Reply with quote
Hi,

The answer is B) but I need explanation....please help!


. Is the positive integer n equal to the square of an integer?
(1) For every prime number p, if p is a divisor of n, then so is p^2.
(2) root n is an integer
Back to top


View user's profile Send private message
gabriel
Managing Director


Joined: 20 Dec 2006
Posts: 660

Thanks given: 84
Thanked 20 times in 19 posts

Location: India
PostPosted: Fri Apr 06, 2007 11:23 am    Post subject: Re: 500 ds test4#17 Reply with quote
dunkin77 wrote:
Hi,

The answer is B) but I need explanation....please help!


. Is the positive integer n equal to the square of an integer?
(1) For every prime number p, if p is a divisor of n, then so is p^2.
(2) root n is an integer


well B is pretty obvious .. if root of n is ann integer that is bcoz n is the square of another intger ..

let me focus on A .. consider a number 2^2*3^2... so the prime numbers that divide n are 2,3 and as the statement says both 2^2 and 3^2 are also factors of n .. in this case n is a square of an integer ...

now consider another number .. 2^3*3^2 ... in this case too the prime factors are 2,3 and also 4 and 9 divide the number but the number is not the square of an integer .. so A does not give a defnite answer .. so is insufficient ...
Back to top


View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    Beat The GMAT Forum Index -> GMAT Math -> Data Sufficiency All times are GMT - 7 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum



"GMAT" and other GMAC™ trademarks are registered trademarks of the Graduate Management Admission Council™. The Graduate Management Admission Council™ does not endorse, nor is it affiliated in any way with the owner or any content on this website. The opinions expressed here are solely those of the author or those of the members of this website. Copyright © 2008 BTG Test Prep, LLC. Powered by phpBB © 2001, 2005 phpBB Group.