Last visit was: 25 Apr 2026, 08:05 It is currently 25 Apr 2026, 08:05
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
enigma123
Joined: 25 Jun 2011
Last visit: 16 Mar 2016
Posts: 392
Own Kudos:
19,868
 [4]
Given Kudos: 217
Status:Finally Done. Admitted in Kellogg for 2015 intake
Location: United Kingdom
Concentration: International Business, Strategy
GMAT 1: 730 Q49 V45
GPA: 2.9
WE:Information Technology (Consulting)
GMAT 1: 730 Q49 V45
Posts: 392
Kudos: 19,868
 [4]
2
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 25 Apr 2026
Posts: 109,827
Own Kudos:
811,209
 [9]
Given Kudos: 105,878
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,827
Kudos: 811,209
 [9]
7
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
General Discussion
User avatar
stonecold
Joined: 12 Aug 2015
Last visit: 09 Apr 2024
Posts: 2,231
Own Kudos:
Given Kudos: 893
GRE 1: Q169 V154
GRE 1: Q169 V154
Posts: 2,231
Kudos: 3,643
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
mvictor
User avatar
Board of Directors
Joined: 17 Jul 2014
Last visit: 14 Jul 2021
Posts: 2,118
Own Kudos:
Given Kudos: 236
Location: United States (IL)
Concentration: Finance, Economics
GMAT 1: 650 Q49 V30
GPA: 3.92
WE:General Management (Transportation)
Products:
GMAT 1: 650 Q49 V30
Posts: 2,118
Kudos: 1,277
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
enigma123
If k is a positive integer, is \(\sqrt{k}\) an integer?

(1) \(1 < \sqrt{k} < 3\)

(2) \(k^2 < 16\)

How come the answer is C?

Statement 1 - The only value K can take is 2. So this is sufficient.

Statement 2 - is not sufficient as -4 < k < 4.

Where I am incorrect guys?

If k is a positive integer, is \(\sqrt{k}\) an integer?

(1) \(1 < \sqrt{k} < 3\). Square the given inequality: \(1<k<9\) --> \(k\) can be 2, 3, 4, 5, 6, 7, or 8. If \(k=4\) then \(\sqrt{k}\) is an integer, for other values it's not an integer. Not sufficient.

(2) \(k^2 < 16\) --> \(-4<k<4\), since it's also given that \(k\) is a positive integer, then \(k\) can be 1, 2 or 3. If \(k=1\) then the answer is YES but if \(k\) is 2 or 3 then the answer is NO. Not sufficient.

(1)+(2) Intersection of the values of \(k\) from (1) and (2) is 2 and 3, \(\sqrt{k}\) is NOT an integer for either of them. Sufficient.

Answer: C.

what a brilliant explanation...I answered E, but now I see why I made the mistake...
i thought that k^2 = 4, therefore sqrt(k) can be either a non-integer or an integer...
User avatar
Basshead
Joined: 09 Jan 2020
Last visit: 07 Feb 2024
Posts: 906
Own Kudos:
Given Kudos: 431
Location: United States
Posts: 906
Kudos: 323
Kudos
Add Kudos
Bookmarks
Bookmark this Post
If k is a positive integer, is \(\sqrt{k}\) an integer?

(1) \(1 < \sqrt{k} < 3\)

\(1 < k < 9\)

K could or could not be an integer. INSUFFICIENT.

(2) \(k^2 < 16\)

Since k must be a positive integer, k can be 1, 2, or 3.

If k is 1, then \(\sqrt{k}\) is an integer. If k = 2 or 3, \(\sqrt{k}\) is not an integer. INSUFFICIENT.

(1&2) \(1 < k < 9\)
k must be 2 or 3. For either number, \(\sqrt{k}\) is NOT an integer. SUFFICIENT.

Answer is C.
Moderators:
Math Expert
109827 posts
498 posts
212 posts