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

It is currently 21 Oct 2014, 06:04

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

PS- Lets see who cracks it.....

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Manager
Manager
avatar
Joined: 28 Jan 2004
Posts: 204
Location: India
Followers: 2

Kudos [?]: 10 [0], given: 4

PS- Lets see who cracks it..... [#permalink] New post 05 Feb 2004, 03:12
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Please show me the right way to do this.

A container contained 80Kg of milk. from this container 8Kg of milk was taken and replaced by water. the process of taking out 8kg of liquid was repeated 2 times. How much milk is now there in the vessel.

A. 54
B. 56
C. 58.32
D. 53.18
E. I m not that smart.....
GMAT Instructor
User avatar
Joined: 07 Jul 2003
Posts: 771
Location: New York NY 10024
Schools: Haas, MFE; Anderson, MBA; USC, MSEE
Followers: 10

Kudos [?]: 32 [0], given: 0

Re: PS- Lets see who cracks it..... [#permalink] New post 05 Feb 2004, 03:42
mdfrahim wrote:
Please show me the right way to do this.

A container contained 80Kg of milk. from this container 8Kg of milk was taken and replaced by water. the process of taking out 8kg of liquid was repeated 2 times. How much milk is now there in the vessel.

A. 54
B. 56
C. 58.32
D. 53.18
E. I m not that smart.....


The way to do this is
1) realize that you remove a "solution" and add "water" which creates a new solution of X% milk.
2) everytime you remove 8kg of the solution, keep track of how much of that solution is milk by multiplying 8kg x X%.
repeat.
3) The amount of milk left is 80kg less that amount you removed.

P.S. strickly speaking, we must assume milk and water have same density.
_________________

Best,

AkamaiBrah
Former Senior Instructor, Manhattan GMAT and VeritasPrep
Vice President, Midtown NYC Investment Bank, Structured Finance IT
MFE, Haas School of Business, UC Berkeley, Class of 2005
MBA, Anderson School of Management, UCLA, Class of 1993

Manager
Manager
avatar
Joined: 28 Jan 2004
Posts: 204
Location: India
Followers: 2

Kudos [?]: 10 [0], given: 4

 [#permalink] New post 05 Feb 2004, 04:42
Some one please do what Akamiah has suggested. I am not able to get anything..its going toooooo complex.
Intern
Intern
avatar
Joined: 29 May 2003
Posts: 13
Followers: 0

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

C is right (I think) [#permalink] New post 05 Feb 2004, 07:01
Actually there is no need to calculate it.

8*3 = 24kg milk, so if we pretend that we remove 8kg of milk only three times there will be 56kg milk left. But now we know that some of what we remove will be water so there has to be more than 56kg of milk left.

Which leads us to C as the only possible answer.
GMAT Club Legend
GMAT Club Legend
avatar
Joined: 15 Dec 2003
Posts: 4318
Followers: 23

Kudos [?]: 171 [0], given: 0

 [#permalink] New post 05 Feb 2004, 07:32
First drain:
8kg of milk taken out. You are left with 72 kg of milk and 8kg of water

Second drain:
The liquid left is with a concentration of 90% (72kg) of milk
Then when you take 8kg out, you are taking 90% milk and 10% water
Therefore, the quantity of milk left will be 72kg * 0.9 = 64.8kg milk after the second drain

Third drain:
Same process. 64.8kg of milk * 0.9 = 58.32kg of milk left
_________________

Best Regards,

Paul

Director
Director
avatar
Joined: 03 Jul 2003
Posts: 656
Followers: 2

Kudos [?]: 15 [0], given: 0

Re: PS- Lets see who cracks it..... [#permalink] New post 05 Feb 2004, 07:42
mdfrahim wrote:
Please show me the right way to do this.

A container contained 80Kg of milk. from this container 8Kg of milk was taken and replaced by water. the process of taking out 8kg of liquid was repeated 2 times. How much milk is now there in the vessel.

A. 54
B. 56
C. 58.32
D. 53.18
E. I m not that smart.....


Good Question. But, the Question should be reworded to
".... This process of taking out 8Kg of liquid was repeated 2 *MORE*
times....".

I interpreted the question as taking 8kg liquid only two times.
Did anyone else interpret in the same way?


Interesting question. Keep these kind of questions flooding the forum !
GMAT Club Legend
GMAT Club Legend
avatar
Joined: 15 Dec 2003
Posts: 4318
Followers: 23

Kudos [?]: 171 [0], given: 0

 [#permalink] New post 05 Feb 2004, 07:51
I agree with you kpadma. It got me confused too as to the number of times the process was repeated. I guess the answer choices gave me the hint.
_________________

Best Regards,

Paul

Senior Manager
Senior Manager
User avatar
Joined: 06 Dec 2003
Posts: 366
Location: India
Followers: 1

Kudos [?]: 3 [0], given: 0

Please ratify ! [#permalink] New post 05 Feb 2004, 09:08
Ans is C: 58.32

milk left after 3rd operation=(1-8/80)^3 * 80


Cheers, Dharmin
Director
Director
User avatar
Joined: 28 Oct 2003
Posts: 503
Location: 55405
Followers: 1

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

 [#permalink] New post 05 Feb 2004, 10:01
kpadma: I agree that the phrasing is suspect, but your correction isn't any better. To be "repeated 2 more times" it must have already been repeated. "Performed two more times" would be the clearest way to ask this.

I know this is PS, not SC, but these little differences are important.
Director
Director
avatar
Joined: 03 Jul 2003
Posts: 656
Followers: 2

Kudos [?]: 15 [0], given: 0

 [#permalink] New post 05 Feb 2004, 10:25
stoolfi wrote:
kpadma: I agree that the phrasing is suspect, but your correction isn't any better. To be "repeated 2 more times" it must have already been repeated. "Performed two more times" would be the clearest way to ask this.

I know this is PS, not SC, but these little differences are important.

Stoolfi: You are most welcome to correct the mistakes!
How else are we going to learn?
SVP
SVP
User avatar
Joined: 30 Oct 2003
Posts: 1798
Location: NewJersey USA
Followers: 4

Kudos [?]: 36 [0], given: 0

 [#permalink] New post 05 Feb 2004, 16:54
I agree with stoolfi about this question. It is not clear whether the diluation occured 2 times or 3 times.
if it occured 2 times then remaining milk is 0.9*0.9 * 80 = 64.8
if it occured 3 times then remaining milk is 0.9*0.9*0.9 * 80 = 58.32

( 8Kg is 10 percent of 80kg so 90% milk remains at each dilution )
Manager
Manager
avatar
Joined: 28 Jan 2004
Posts: 204
Location: India
Followers: 2

Kudos [?]: 10 [0], given: 4

 [#permalink] New post 05 Feb 2004, 21:57
Well...the correct answer is 58.32. Anand the dilution has occured 3 times.
  [#permalink] 05 Feb 2004, 21:57
    Similar topics Author Replies Last post
Similar
Topics:
Experts publish their posts in the topic Brutal period is starting,lets see who is the boss!!!! fatihaysu 36 31 Aug 2010, 16:38
2 Please Crack the Math (PS) Question! Anyone! Thanks ;) uzonwagba 4 21 Jul 2009, 21:07
Crack the GMAT question on PS: gmatprep09 2 07 May 2009, 14:22
CR- lets see how you predict shahnandan 0 02 Nov 2005, 07:00
let see how it goes... nakib77 5 30 Sep 2005, 10:09
Display posts from previous: Sort by

PS- Lets see who cracks it.....

  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®.