GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 24 Sep 2018, 18:23

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

The positive integer p is divisible by 11. If √p is an integer divisib

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Intern
Intern
avatar
B
Joined: 06 Jul 2013
Posts: 43
Location: United States
CAT Tests
The positive integer p is divisible by 11. If √p is an integer divisib  [#permalink]

Show Tags

New post Updated on: 05 Jul 2018, 11:10
00:00
A
B
C
D
E

Difficulty:

  45% (medium)

Question Stats:

43% (00:32) correct 57% (01:36) wrong based on 7 sessions

HideShow timer Statistics

The positive integer p is divisible by 11. If √p is an integer divisible by 3, which of the following must be a factor of p/11?

(A) 9
(B) 14
(C) 15
(D) 33
(E) 99

Originally posted by TippingPoint93 on 05 Jul 2018, 10:49.
Last edited by Bunuel on 05 Jul 2018, 11:10, edited 1 time in total.
Renamed the topic, edited the question and added the OA.
Math Expert
User avatar
V
Joined: 02 Sep 2009
Posts: 49430
The positive integer p is divisible by 11. If √p is an integer divisib  [#permalink]

Show Tags

New post 05 Jul 2018, 11:10
1
TippingPoint93 wrote:
The positive integer p is divisible by 11. If √p is an integer divisible by 3, which of the following must be a factor of p/11?

(A) 9
(B) 14
(C) 15
(D) 33
(E) 99


√p = 3k;

p = 9k^2. So, p is a multiple of 9.

Since we also know that p is a multiple of 11 too, then p must be a multiple of both 9 and 11, so a multiple of the LCM of 9 and 11, which is 99.

p/11 = 99x/11 = 9x. Thus, p/11 must be a multiple of 9.

Answer: A.

P.S. Please provide the OA when posting a question.
_________________

New to the Math Forum?
Please read this: Ultimate GMAT Quantitative Megathread | All You Need for Quant | PLEASE READ AND FOLLOW: 12 Rules for Posting!!!

Resources:
GMAT Math Book | Triangles | Polygons | Coordinate Geometry | Factorials | Circles | Number Theory | Remainders; 8. Overlapping Sets | PDF of Math Book; 10. Remainders | GMAT Prep Software Analysis | SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) | Tricky questions from previous years.

Collection of Questions:
PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat

DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.


What are GMAT Club Tests?
Extra-hard Quant Tests with Brilliant Analytics

Intern
Intern
avatar
B
Joined: 06 Jul 2013
Posts: 43
Location: United States
CAT Tests
Re: The positive integer p is divisible by 11. If √p is an integer divisib  [#permalink]

Show Tags

New post 05 Jul 2018, 11:24
Bunuel wrote:
TippingPoint93 wrote:
The positive integer p is divisible by 11. If √p is an integer divisible by 3, which of the following must be a factor of p/11?

(A) 9
(B) 14
(C) 15
(D) 33
(E) 99


√p = 3k;

p = 9k^2. So, p is a multiple of 9.

Since we also know that p is a multiple of 11 too, then p must be a multiple of both 9 and 11, so a multiple of the LCM of 9 and 11, which is 99.

p/11 = 99x/11 = 9x. Thus, p/11 must be a multiple of 9.

Answer: A.

P.S. Please provide the OA when posting a question.


Thanks for the response, Bunuel. Apologies for the lack of OA. I had posted from my phone. The OA is A.


Could you please tell me where I’ve gone wrong?

If 11 is a factor of p, and sqrt(p) is an integer, then doesn’t that mean that 11 is also a factor of sqrt(p)? And hence p/11 would also be a multiple of 11? Making 3x11=33 also a possible answer?


Sent from my iPhone using GMAT Club Forum mobile app
GMAT Club Bot
Re: The positive integer p is divisible by 11. If √p is an integer divisib &nbs [#permalink] 05 Jul 2018, 11:24
Display posts from previous: Sort by

The positive integer p is divisible by 11. If √p is an integer divisib

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  

Events & Promotions

PREV
NEXT


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.