 It is currently 22 Nov 2019, 15:45 ### 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

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. # If n is an integer and 3n/7 is a perfect square  Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:
Founder  Joined: 18 Apr 2015
Posts: 8831
Followers: 176

Kudos [?]: 2058 , given: 8149

If n is an integer and 3n/7 is a perfect square [#permalink]
Expert's post 00:00

Question Stats: 77% (00:28) correct 22% (00:16) wrong based on 31 sessions
If n is an integer and $$\frac{3n}{7}$$ is a perfect square, the smallest possible value of n is

A. 3

B. 7

C. 21

D. 42

E. 147
[Reveal] Spoiler: OA

_________________

Need Practice? 20 Free GRE Quant Tests available for free with 20 Kudos
GRE Prep Club Members of the Month: Each member of the month will get three months free access of GRE Prep Club tests. Intern Joined: 29 Jun 2018
Posts: 21
Followers: 0

Kudos [?]: 15  , given: 0

Re: If n is an integer and 3n/7 is a perfect square [#permalink]
1
KUDOS
Just plug the value and see the smallest value which will give a square. 21 is the answer which gives 9 (a square of 3)
Manager  Joined: 06 Jun 2018
Posts: 94
Followers: 1

Kudos [?]: 64 , given: 0

Re: If n is an integer and 3n/7 is a perfect square [#permalink]
Carcass wrote:
If n is an integer and $$\frac{3n}{7}$$ is a perfect square, the smallest possible value of n is

A. 3

B. 7

C. 21

D. 42

E. 147

$$\frac{3n}{7}$$ = perfect square.

Note: As 3 is not divisible by 7 , n must be a multiple of 7.

So, we must pick up a number in such a manner thus after division still we can form a perfect square.

27 = 7*3

So,

$$\frac{3*21}{7}$$ = $$3^2$$

Thus the best answer is C.
Intern Joined: 19 Mar 2018
Posts: 25
Followers: 1

Kudos [?]: 9 , given: 11

Re: If n is an integer and 3n/7 is a perfect square [#permalink]
This has options so we can plug in and check:
1) 3(3)/ 7 = NO
2) 3(7)/ 7 = NO
3) 3 (7 x 3)/ 7 = 9 = YES

Intern Joined: 19 Mar 2018
Posts: 25
Followers: 1

Kudos [?]: 9 , given: 11

Re: If n is an integer and 3n/7 is a perfect square [#permalink]
This has options so we can plug in and check:
1) 3(3)/ 7 = NO
2) 3(7)/ 7 = NO
3) 3 (7 x 3)/ 7 = 9 = YES Re: If n is an integer and 3n/7 is a perfect square   [#permalink] 13 Sep 2018, 12:41
Display posts from previous: Sort by

# If n is an integer and 3n/7 is a perfect square  Question banks Downloads My Bookmarks Reviews Important topics  Powered by phpBB © phpBB Group Kindly note that the GRE® test is a registered trademark of the Educational Testing Service®, and this site has neither been reviewed nor endorsed by ETS®.