Last visit was: 21 May 2025, 00:39 It is currently 21 May 2025, 00:39
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
User avatar
shikhar
Joined: 14 Feb 2012
Last visit: 26 May 2013
Posts: 81
Own Kudos:
1,119
 [28]
Given Kudos: 7
Posts: 81
Kudos: 1,119
 [28]
5
Kudos
Add Kudos
23
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 21 May 2025
Posts: 101,585
Own Kudos:
725,879
 [6]
Given Kudos: 93,577
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 101,585
Kudos: 725,879
 [6]
3
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
General Discussion
avatar
ashiima86
Joined: 05 May 2013
Last visit: 25 Jan 2014
Posts: 1
Own Kudos:
Posts: 1
Kudos: 5
Kudos
Add Kudos
Bookmarks
Bookmark this Post
avatar
pritish2301
Joined: 24 Sep 2012
Last visit: 02 Jan 2014
Posts: 23
Own Kudos:
Given Kudos: 76
Posts: 23
Kudos: 16
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi Ashima,

This is how I verified statement 1.

Take n = 36, p = 2
If p is a divisor of n, then so is p2. Check for p^2 => 2^2 => 4, 36 is divisible by 4. - OK

Take n = 15, p = 3
If p is a divisor of n, then so is p2. Check for p^2 => 3^2 => 9, 15 is not divisible by 9 - Not OK

Hence statement 1 is insufficient. Hope this is OK.

Maybe Bunuel can help us better.

Regards,
Pritish
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 21 May 2025
Posts: 101,585
Own Kudos:
Given Kudos: 93,577
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 101,585
Kudos: 725,879
Kudos
Add Kudos
Bookmarks
Bookmark this Post
ashiima86
Bunuel
shikhar
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 p2.
(2) is an integer.

Is the positive integer n equal to the square of an integer?

Question: is \(n=integer^2\)? So, basically we are asked whether \(n\) is a perfect square (a perfect square, is an integer that can be written as the square of some other integer. For example 16=4^2, is a perfect square.).

(1) For every prime number p, if p is a divisor of n, then so is p^2 --> if \(n=2^2\) then the answer is YES but if \(n=2^3\) then the answer is NO (notice that in both case prime number 2 as well as 2^2 are divisors of n, so our condition is satisfied). Not sufficient.

(2) \(\sqrt{n}\) is an integer --> \(\sqrt{n}=integer\) --> \(n=integer^2\). Sufficient.

Answer: B.


ST 1-isnt this telling you all the prime factors of n are raised to even powers which makes n a square number-i got wrong can you please re-explain.

No, the first statement says that if a prime number p is a factor of n, then so is p^2, which means that the power of p is more than or equal to 2: it could be 2, 3, ... So, n is not necessarily a prefect square. For example, if \(n=2^2\) then the answer is YES but if \(n=2^3\) then the answer is NO (notice that in both case prime number 2 as well as 2^2 are divisors of n, so our condition is satisfied).

Hope it's clear.
User avatar
Bluelagoon
Joined: 21 Jan 2010
Last visit: 03 Sep 2015
Posts: 192
Own Kudos:
Given Kudos: 12
Kudos
Add Kudos
Bookmarks
Bookmark this Post
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

From 1 ) If p=4, than 16 is also a factor. Which can qualify n to be a perfect square.But if p=2 than 4 is also a factor. However we can't say if n is square of an integer or not. Hence Insufficient.

2) If root n is an integer -> N has to be the square of an integer. Sufficient.

Answer B.
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 36,909
Own Kudos:
Posts: 36,909
Kudos: 990
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Moderator:
Math Expert
101578 posts