It is currently Mon Mar 15, 2010 5:31 am
Image
GMAT ToolKit becomes an open platform for test takers and Prep companies!

Additional 236 questions from our partner Manhattan Review are already available. Update your application for free.

Manhattan Review Discount: Save 10% and free GMAT Club Tests




Post new topic Reply to topic  [ 6 posts ]  Bookmark and Share
Author Message
 Post subject: M24 Q 24 [#permalink]
PostPosted: Thu Mar 12, 2009 1:54 pm 
Offline
Math & Verbal GMAT Forum Moderator
Math & Verbal GMAT Forum Moderator
User avatar

Joined: Sat Jul 05, 2008
Posts: 1575

Kudos (?): 101 (0), given: 1

I pulled this off but I want to hear from folks on their approaches

In normal printing mode, 20 printers can print 100 pages in 3 minutes. In economy mode, printers work 20% faster than in normal mode. How many printers are required to print 180 pages in 3 minutes in economy mode?

(C) 2008 GMAT Club - m24#24

* 25
* 28
* 29
* 30
* 32

[Reveal] Spoiler: OA
D


Source: GMAT Club Tests - hardest GMAT Questions

_________________
Please underline SC questions.

Please Do not post OA along with the Q.

Give and take Kudos.


Top
 Profile  
 
 Post subject: Re: M24 Q 24 [#permalink]
PostPosted: Thu Mar 12, 2009 5:55 pm 
Offline
CEO in training
CEO in training
User avatar

Joined: Wed Nov 07, 2007
Posts: 2201
Location: New York

Kudos (?): 166 (0), given: 2

icandy wrote:
I pulled this off but I want to hear from folks on their approaches

In normal printing mode, 20 printers can print 100 pages in 3 minutes. In economy mode, printers work 20% faster than in normal mode. How many printers are required to print 180 pages in 3 minutes in economy mode?

(C) 2008 GMAT Club - m24#24

* 25
* 28
* 29
* 30
* 32


normal mod = 100/20*3 = 5/3 PAGES/printer/minute

economy mode printer rate = 5/3 *1.2 = 2 pages/printer/minute

priner rate for 3 minutes = 6 pages/printer = 180 pages /30 printers

30

D

_________________
Your attitude determines your altitude
Smiling wins more friends than frowning


Top
 Profile  
 
 Post subject: Re: M24 Q 24 [#permalink]
PostPosted: Mon Mar 16, 2009 8:46 am 
Offline
Manager
Manager

Joined: Sat Jul 07, 2007
Posts: 169

Kudos (?): 1 (0), given: 0

icandy wrote:
I pulled this off but I want to hear from folks on their approaches

In normal printing mode, 20 printers can print 100 pages in 3 minutes. In economy mode, printers work 20% faster than in normal mode. How many printers are required to print 180 pages in 3 minutes in economy mode?

(C) 2008 GMAT Club - m24#24

* 25
* 28
* 29
* 30
* 32


Method:

1) First find out the time required to print 1 page in 3 Minutes (here 3 Minutes because answer ask for the same) with 1 printer and you will find one printer prints 6 pages in 3 minutes after their percentage increase in economical speed.

(100 / 20) * (120 / 100) = 6 pages.

2) Once you find this it is easy to find for 180 pages how many printer requires. (30).

2) Once you find 6


Top
 Profile  
 
 Post subject: Re: M24 Q 24 [#permalink]
PostPosted: Fri Mar 20, 2009 12:18 pm 
Offline
Intern
Intern

Joined: Fri Mar 06, 2009
Posts: 2

Kudos (?): 0 (0), given: 0

In economy mode printers print 20% faster. Hence 20 printers will print 120 pages in 3 mins. You want 1.5 times of 120 pages, hence you multiply 1.5 * 20 printers (and don't touch the time at all, as we want to find out the number of pages in 3 mins) = 30 printers.

Hence, ANS - 30 printers


Top
 Profile  
 
 Post subject: Re: M24 Q 24 [#permalink]
PostPosted: Sun Apr 05, 2009 2:14 am 
Offline
Major Shareholder
Major Shareholder
User avatar

Joined: Tue Apr 01, 2008
Posts: 988
Location: Bangalore, Baroda

Kudos (?): 69 (0), given: 17

Normal mode rate = 100/(3*20)
Economy mode rate = 1.20 * 100/(3*20)

Now, let x be the number of economy mode printers.
Adding rates of all printers = Combined rate of printers

x * 1.20 * 100/(3*20) = 180/3
=>x = 30


Top
 Profile  
 
 Post subject: Re: M24 Q 24 [#permalink]
PostPosted: Thu Apr 09, 2009 11:29 pm 
Offline
Manager
Manager
User avatar

Joined: Fri Nov 14, 2008
Posts: 217
Schools: Stanford! (Do I have a chance?)

Kudos (?): 8 (0), given: 3

20 printer, 100 page, 3 minutes
1 printer, 5 page, 3 minutes
in economy it is 20% faster
so,
1 printer, 5+1 page , 3 minutes
30 printer, 180 page, 3 minutes.
D is the answer
icandy wrote:
I pulled this off but I want to hear from folks on their approaches

In normal printing mode, 20 printers can print 100 pages in 3 minutes. In economy mode, printers work 20% faster than in normal mode. How many printers are required to print 180 pages in 3 minutes in economy mode?

(C) 2008 GMAT Club - m24#24

* 25
* 28
* 29
* 30
* 32


Top
 Profile  
 
Online
gmatclubot
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 


Who is online

Users browsing this forum: No registered users and 0 guests


Search for:
Jump to:




GMAT Club MBA Forum Home | Sitemap | About | Privacy Policy | Terms and Conditions | GMAT Club Rules | Contact
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
Kindly note that GMAT (C) is a registered trademark of the Graduate Management Admission Council, and this site has neither been reviewed nor endorsed by GMAC.