Find all School-related info fast with the new School-Specific MBA Forum

It is currently 23 Jul 2014, 13:01

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.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Math DS (m05q29)

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Director
Director
avatar
Joined: 11 Jun 2007
Posts: 649
Followers: 3

Kudos [?]: 34 [0], given: 0

GMAT Tests User
Math DS (m05q29) [#permalink] New post 18 Oct 2007, 10:27
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Is \frac{4Q}{11} a positive integer?

1. Q is a prime number
2. 2Q is divisible by 11

[Reveal] Spoiler: OA
C

Source: GMAT Club Tests - hardest GMAT questions
Kaplan GMAT Prep Discount CodesKnewton GMAT Discount CodesManhattan GMAT Discount Codes
Manager
Manager
User avatar
Joined: 02 Aug 2007
Posts: 146
Followers: 1

Kudos [?]: 9 [0], given: 0

 [#permalink] New post 18 Oct 2007, 10:39
B.
The question is asking whether Q is a multiple of 11.

1) Q as a prime number does not help us in answer the question.
INSUFF

2) 2Q is a multiple of 11, so 4Q should also be a multiple of 11.
SUFFICIENT
Director
Director
avatar
Joined: 11 Jun 2007
Posts: 649
Followers: 3

Kudos [?]: 34 [0], given: 0

GMAT Tests User
 [#permalink] New post 18 Oct 2007, 12:30
yuefei wrote:
B.
The question is asking whether Q is a multiple of 11.

1) Q as a prime number does not help us in answer the question.
INSUFF

2) 2Q is a multiple of 11, so 4Q should also be a multiple of 11.
SUFFICIENT


I got the same answer but that is not the OA.
Guys, any other answers?
Manager
Manager
avatar
Joined: 30 Jan 2006
Posts: 64
Followers: 1

Kudos [?]: 2 [0], given: 0

 [#permalink] New post 18 Oct 2007, 15:26
I think the answer is C.

The reason is the question is asking if 4Q/11 is a +ive integer. 2Q/11 is divisble by 11 but it can be -ive also.
Any other thoughts please.
Director
Director
avatar
Joined: 11 Jun 2007
Posts: 649
Followers: 3

Kudos [?]: 34 [0], given: 0

GMAT Tests User
 [#permalink] New post 18 Oct 2007, 15:41
smily_buddy wrote:
I think the answer is C.

The reason is the question is asking if 4Q/11 is a +ive integer. 2Q/11 is divisble by 11 but it can be -ive also.
Any other thoughts please.


There is the missing link. You are right. That is why we need both conditions. (C) is the OA.
VP
VP
User avatar
Joined: 09 Jul 2007
Posts: 1111
Location: London
Followers: 6

Kudos [?]: 63 [0], given: 0

GMAT Tests User
 [#permalink] New post 18 Oct 2007, 16:40
1. prime number, it can give us a non integer
2. can be negative and positive

applied together 1 and 2. we say that prime cannot be negative and 2 gives us multiple so C
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jul 2004
Posts: 5097
Location: Singapore
Followers: 16

Kudos [?]: 131 [0], given: 0

GMAT Tests User
 [#permalink] New post 18 Oct 2007, 17:51
St1:
If Q = 11, then 4Q/11 is a positive integer.
If Q = 2, then 4Q/11 is not a positive integer.
Insufficient.

St2:
2Q/11 = integer.
If Q = 22, then 2Q/11 = integer and 4Q/11 = positive integer
if Q = -33/2, then 2Q/11 = integer but 4Q/11 != positive integer.
Insufficient.

St1 and St2:
Q = 11, then 2Q/11 = integer and 4Q/11 = positive integer.
Sufficient.


Ans C
Intern
Intern
avatar
Joined: 06 Sep 2009
Posts: 24
Location: Mumbai
Followers: 0

Kudos [?]: 2 [0], given: 9

GMAT Tests User
Re: [#permalink] New post 25 Oct 2009, 05:20
Ravshonbek wrote:
1. prime number, it can give us a non integer
2. can be negative and positive

applied together 1 and 2. we say that prime cannot be negative and 2 gives us multiple so C



Little confused guys, prime numbers cannot be negative ? It means -11 is not qualified as a prime number ?
CEO
CEO
User avatar
Joined: 29 Aug 2007
Posts: 2501
Followers: 51

Kudos [?]: 483 [0], given: 19

GMAT Tests User
Re: Math DS (m05q29) [#permalink] New post 25 Oct 2009, 09:45
eyunni wrote:
Is 4Q/11 a positive integer?

(1) Q is a prime number
(2) 2Q is divisible by 11



1: Q could be 2 or 3 or 5 or 7 or 11 or 13. NSF..
2: Q could be -ve, 0 or +ve. For ex: -11 or -5.50 or 0 or 5.50 or 11 or any multiples of 11. NSF..

1&2: Q must be a prime and 2Q must be divisible by 11.

Q must be a prime eliminates the chances that Q is a -ve, 0 and fraction.
Given that Q is a prime and 2Q must be divisible by 11 eliminate the chances that Q is other than 11.

Therefore Q = 11 and 4Q/11 is a +ve integer i.e. 4.

Thats a good question though....

_________________

Verbal: new-to-the-verbal-forum-please-read-this-first-77546.html
Math: new-to-the-math-forum-please-read-this-first-77764.html
Gmat: everything-you-need-to-prepare-for-the-gmat-revised-77983.html


GT

Intern
Intern
avatar
Joined: 14 Sep 2009
Posts: 26
Location: New York, NY
Followers: 0

Kudos [?]: 7 [0], given: 5

Re: Math DS (m05q29) [#permalink] New post 29 Nov 2009, 07:16
Hey I know I'm joining this thread really really late - but can anyone confirm whether prime numbers can be negative?

I checked the Wikipedia Prime page (I can't post the link!) but I didn't see anything definitive.
Manager
Manager
avatar
Joined: 17 Jan 2010
Posts: 59
Concentration: Entrepreneurship, Strategy
GMAT 1: 730 Q49 V41
WE: Consulting (Consulting)
Followers: 0

Kudos [?]: 33 [0], given: 6

GMAT Tests User
Re: Math DS (m05q29) [#permalink] New post 26 Jun 2010, 09:16
http://mathforum.org/library/drmath/view/55940.html

- Explanation as to why there are no negative prime numbers.

_________________

My GMAT story: 730 Debrief

Intern
Intern
avatar
Joined: 12 Mar 2010
Posts: 10
GMAT 1: 710 Q48 V38
GMAT 2: Q V
GMAT 3: Q V
Followers: 0

Kudos [?]: 6 [0], given: 0

Re: Math DS (m05q29) [#permalink] New post 26 Jun 2010, 17:12
C

1) Q can be 11 => it works or Q can be 3 => is not good, hence insufficient
2) 2Q is divisible by B, but we don't know if the result of this division is a positive integer, hence insufficient

1 & 2 together work
Expert Post
Math Expert
User avatar
Joined: 02 Sep 2009
Posts: 18705
Followers: 3236

Kudos [?]: 22277 [0], given: 2611

Re: Math DS (m05q29) [#permalink] New post 15 Apr 2012, 12:53
Expert's post
eyunni wrote:
Is \frac{4Q}{11} a positive integer?

1. Q is a prime number
2. 2Q is divisible by 11

[Reveal] Spoiler: OA
C

Source: GMAT Club Tests - hardest GMAT questions


(1) q is a prime number --> if q=2 then the answer is NO but if q=11 then the answer is YES. Not sufficient.

(2) 2q is divisible by 11 --> \frac{2q}{11}=integer --> 2*\frac{2q}{11}=\frac{4q}{11}=2*integer=integer, but we don't know whether this integer is positive or not: consider q=0 and q=11. Not sufficient.

(1)+(2) Since q is a prime number and 2q is divisible by 11, then q must be equal to 11 (no other prime but 11 will yield integer result for \frac{2q}{11} ) --> \frac{4q}{11}=4. Sufficient.

Answer: C.

_________________

NEW TO MATH FORUM? PLEASE READ THIS: ALL YOU NEED FOR QUANT!!!

PLEASE READ AND FOLLOW: 11 Rules for Posting!!!

RESOURCES: [GMAT MATH BOOK]; 1. Triangles; 2. Polygons; 3. Coordinate Geometry; 4. Factorials; 5. Circles; 6. Number Theory; 7. Remainders; 8. Overlapping Sets; 9. PDF of Math Book; 10. Remainders; 11. GMAT Prep Software Analysis NEW!!!; 12. SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS) NEW!!!; 12. Tricky questions from previous years. NEW!!!;

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?
25 extra-hard Quant Tests

Get the best GMAT Prep Resources with GMAT Club Premium Membership

Re: Math DS (m05q29)   [#permalink] 15 Apr 2012, 12:53
    Similar topics Author Replies Last post
Similar
Topics:
m05 Q29 suhasrao 1 30 Jul 2010, 18:17
Experts publish their posts in the topic Math DS (m05q29) eyunni 12 18 Oct 2007, 10:27
1 GMATPRep Maths DS rgajare14 1 16 Mar 2008, 14:32
Math DS questions - Help with solution vidyanan 3 13 Jun 2007, 07:11
GMATPrep Question - Math_DS shinewine 4 19 Aug 2006, 04:17
Display posts from previous: Sort by

Math DS (m05q29)

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

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

Powered by phpBB © phpBB Group and phpBB SEO

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®.