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

It is currently 21 Aug 2014, 12:03

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

3 GMAT Prep DS - Need help Please

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Intern
Intern
avatar
Joined: 01 Mar 2006
Posts: 1
Followers: 0

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

3 GMAT Prep DS - Need help Please [#permalink] New post 28 May 2007, 17:04
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Any help in solving these questions is appreciated ..
Attachments

TocheckGMATPrep1.doc [162.5 KiB]
Downloaded 82 times

To download please login or register as a user


Last edited by anujkm on 30 May 2007, 18:59, edited 1 time in total.
Director
Director
avatar
Joined: 12 Jun 2006
Posts: 539
Followers: 1

Kudos [?]: 11 [0], given: 1

GMAT Tests User
 [#permalink] New post 28 May 2007, 20:31
My answer is A:
h(n) = the prod. of all the even integers from 2 - n.
h(100) = the prod. of all the even integers from 2 - 100; 2(4)6(8) ..... = 2(2*2)(2*3)(2*2*2*) ....
p is defined as the smallest prime factor of h(100)+1. the smalles prime factor of h(100), which is the product of all the even integers b/w 2 and 100, is 2. 2 + 1 =3.
Intern
Intern
avatar
Joined: 16 May 2007
Posts: 18
Followers: 0

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

 [#permalink] New post 29 May 2007, 09:26
I will skip the first Q as I have no explanation for the answer. It's crazy that you can get that kind of a Q so early:)

For #2:

Since students either like or dislike either food (i will abreviate them "LB" and "BS"), by knowing what they don't like you actually know what they like.

We need the # of students who dislike LB but like BS

You know that 2/3 of the students dislike LB and of those 2/5 like BS (1-3/5). So, in essence, all you need to know is the actual number of students who dislike LB.

(1) Sufficient. Knowing the total number of students in the cafeteria, you can find the # of the students who dislike LB. (120*2/3 = 80)

(2) Sufficient. Number of students who like LB = 1/3 of all students = 40.
You can use that to find the number of students who dislike LB (80).

Answer D
Intern
Intern
avatar
Joined: 16 May 2007
Posts: 18
Followers: 0

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

 [#permalink] New post 29 May 2007, 09:32
For Q #3:

The problem tells you that z/y and y/x are integers. I will refer to this as (M)


(1) Sufficient. For zx to be even, at least one of the numbers has to be an even number. However, for (M) to hold true z cannot be an odd number. Which means, it has to be even.

(2) Sufficient. Odd numbers are not divisible by even numbers, so if y is even then z has to be even.

Answer D
Director
Director
User avatar
Joined: 03 Sep 2006
Posts: 893
Followers: 6

Kudos [?]: 108 [0], given: 33

Re: 3 GMAT Prep DS - Need help Please [#permalink] New post 29 May 2007, 18:30
anujkm wrote:
Any help in solving these questions is appreciated ..


ANswer for the question 1 is straight away result frmo Wilson's Theroem. Please check Wilson's theorem in WIkipedia and remember it.
Director
Director
User avatar
Joined: 03 Sep 2006
Posts: 893
Followers: 6

Kudos [?]: 108 [0], given: 33

Re: 3 GMAT Prep DS - Need help Please [#permalink] New post 29 May 2007, 18:44
anujkm wrote:
Any help in solving these questions is appreciated ..


Please remember this.... WILSON's THEOREM

p divides (p-1)!+1 if p is prime. The converse is also true. For instance, 7 is prime, and 7 divides (6!)+1=721





.
Director
Director
User avatar
Joined: 03 Sep 2006
Posts: 893
Followers: 6

Kudos [?]: 108 [0], given: 33

 [#permalink] New post 29 May 2007, 18:49
joroivanov wrote:
I will skip the first Q as I have no explanation for the answer. It's crazy that you can get that kind of a Q so early:)

For #2:

Since students either like or dislike either food (i will abreviate them "LB" and "BS"), by knowing what they don't like you actually know what they like.

We need the # of students who dislike LB but like BS

You know that 2/3 of the students dislike LB and of those 2/5 like BS (1-3/5). So, in essence, all you need to know is the actual number of students who dislike LB.

(1) Sufficient. Knowing the total number of students in the cafeteria, you can find the # of the students who dislike LB. (120*2/3 = 80)

(2) Sufficient. Number of students who like LB = 1/3 of all students = 40.
You can use that to find the number of students who dislike LB (80).

Answer D


the key as you mentioned is by knowing what they don't like you actually know what they like.
Director
Director
User avatar
Joined: 03 Sep 2006
Posts: 893
Followers: 6

Kudos [?]: 108 [0], given: 33

 [#permalink] New post 29 May 2007, 18:54
joroivanov wrote:
For Q #3:

The problem tells you that z/y and y/x are integers. I will refer to this as (M)


(1) Sufficient. For zx to be even, at least one of the numbers has to be an even number. However, for (M) to hold true z cannot be an odd number. Which means, it has to be even.

(2) Sufficient. Odd numbers are not divisible by even numbers, so if y is even then z has to be even.

Answer D


Is there no possibility that Z might be odd number?? :roll:
Director
Director
User avatar
Joined: 03 Sep 2006
Posts: 893
Followers: 6

Kudos [?]: 108 [0], given: 33

Re: 3 GMAT Prep DS - Need help Please [#permalink] New post 29 May 2007, 18:55
anujkm wrote:
Any help in solving these questions is appreciated ..


You've attached the same file twice. Please remove one of them.
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jul 2004
Posts: 5097
Location: Singapore
Followers: 17

Kudos [?]: 136 [0], given: 0

GMAT Tests User
 [#permalink] New post 29 May 2007, 19:15
Question 1 has been extensively discussed in this forum. You can do a search and find the solutions.
Intern
Intern
avatar
Joined: 16 May 2007
Posts: 18
Followers: 0

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

 [#permalink] New post 29 May 2007, 19:17
LM - I think not. :)

if zx is the product of an odd number z and an even number x, then what is stated in the question stem wouldn't hold true (z/y and y/x wouldn't be integers).

If we assume that z is odd, for zx to be even, x has to be even. But then for z/y to be an integer, y has to be odd. However, if y is odd, for y/x to be an integer x has to be odd, which contradicts our first assumption (that x is even).



LM wrote:
joroivanov wrote:
For Q #3:

The problem tells you that z/y and y/x are integers. I will refer to this as (M)


(1) Sufficient. For zx to be even, at least one of the numbers has to be an even number. However, for (M) to hold true z cannot be an odd number. Which means, it has to be even.

(2) Sufficient. Odd numbers are not divisible by even numbers, so if y is even then z has to be even.

Answer D


Is there no possibility that Z might be odd number?? :roll:
Intern
Intern
avatar
Joined: 03 Apr 2006
Posts: 46
Followers: 0

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

GMAT Tests User
 [#permalink] New post 29 May 2007, 19:58
Quote:
Question 1 has been extensively discussed in this forum. You can do a search and find the solutions.


does anyone have a link? I am having trouble finding the past discussion
Intern
Intern
avatar
Joined: 03 Apr 2006
Posts: 46
Followers: 0

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

GMAT Tests User
 [#permalink] New post 30 May 2007, 06:26
can someone please explain number one or show me the link for the past discussions.
  [#permalink] 30 May 2007, 06:26
    Similar topics Author Replies Last post
Similar
Topics:
Experts publish their posts in the topic Need help on GMAT prep ebhabookworm 2 22 Jun 2012, 22:19
GMAT-Prep DS3 vivektripathi 1 17 Jan 2009, 03:04
DS 3 gmat prep Balvinder 7 07 Nov 2007, 05:09
3 Questions on GMAT Prep / please help me!! posull78 4 28 Oct 2007, 09:56
GMAT Prep: DS3 compuser1978 6 29 Dec 2006, 06:34
Display posts from previous: Sort by

3 GMAT Prep DS - Need help Please

  Question banks Downloads My Bookmarks Reviews Important topics  


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®.