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

It is currently 18 Apr 2014, 06:01

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

for a certain job,A and B together worked for 6/5 hours, B

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
CEO
CEO
Joined: 15 Aug 2003
Posts: 3470
Followers: 57

Kudos [?]: 649 [0], given: 781

for a certain job,A and B together worked for 6/5 hours, B [#permalink] New post 18 Sep 2003, 11:44
00:00
A
B
C
D
E

Difficulty:

  5% (low)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
for a certain job,A and B together worked for 6/5 hours,
B and C worked for3/2 hours, A and C worked for 2 hours. If all of
them work simultaneously, how many hours can this job be done?
Intern
Intern
Joined: 17 Sep 2003
Posts: 22
Location: GMAT Maze, Chaos.
Followers: 0

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

 [#permalink] New post 18 Sep 2003, 15:24
1/2 hour, is that correct ?


5/6 + 2/3 + 1/2 = 2, so 1/2.
Intern
Intern
Joined: 28 Aug 2003
Posts: 36
Location: USA
Followers: 0

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

Re: PS : Work [#permalink] New post 18 Sep 2003, 15:29
praetorian123 wrote:
for a certain job,A and B together worked for 6/5 hours,
B and C worked for3/2 hours, A and C worked for 2 hours. If all of
them work simultaneously, how many hours can this job be done?


Not sure if this is the best explanation, but I will try...

In one hour A and B together can finish 5/6 of the job
In one hour B and C together can finish 2/3 of the job
In one hour C and A together can finish 1/2 of the job

So, if we add all these up:

In one hour 2 A's, 2 B's and 2 C's can finish (5/6 + 2/3 + 1/2) = 2 times the job.

So, A, B and C can finish the job in 1 hour.

Praet, is this answer correct. For the benefit of everyone, maybe you can explain the answer better than I did. Thanks.
SVP
SVP
User avatar
Joined: 30 Oct 2003
Posts: 1799
Location: NewJersey USA
Followers: 3

Kudos [?]: 29 [0], given: 0

GMAT Tests User
 [#permalink] New post 17 Jan 2004, 11:23
(A+B) + (B+C) + (C+A) = 6/5+3/2+2 = 47/10
In this time 3 times work is done
2A+2B+2C will do one job in 47/30 hours
so
A+B+C will need 47/60 hrs to do one job, working together

Thus they need 47 minutes to complete one job.
Director
Director
User avatar
Joined: 28 Oct 2003
Posts: 503
Location: 55405
Followers: 1

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

GMAT Tests User
 [#permalink] New post 17 Jan 2004, 11:33
Praet,

I think everyone is confused by your syntax.

Did the three of them complete the job once total or once each?

Do you mean that it takes A and B 6/5 hrs, working together, to do the entire job?

Would you mind restating the question?
Intern
Intern
User avatar
Joined: 01 Dec 2003
Posts: 35
Location: infront of my LCD
Followers: 0

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

 [#permalink] New post 17 Jan 2004, 12:02
I got 1 hour

1/A + 1/B = 5/6

1/B + 1/C = 2/3

1/A + 1/C = 1/2

A = 3 , B = 2, C = 6

so...

1/2 + 1/3 + 1/6 = 1

Dont know if this is correct, plus it took me a bit of time.
SVP
SVP
User avatar
Joined: 30 Oct 2003
Posts: 1799
Location: NewJersey USA
Followers: 3

Kudos [?]: 29 [0], given: 0

GMAT Tests User
 [#permalink] New post 17 Jan 2004, 12:08
I have a feeling that Praetorian is off this forum. Many Q without answers and no replies from him.

Hmm,
calnhob's work seems right.

Hi stoolfi,

what is your interpretation of the problem and what is your answer ?
Director
Director
User avatar
Joined: 28 Oct 2003
Posts: 503
Location: 55405
Followers: 1

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

GMAT Tests User
 [#permalink] New post 17 Jan 2004, 12:16
anand,

I interpret the question the same way that you do-- and I think your approach is right.

But 47 minutes is an ugly answer. I bet calnhob has interpreted the syntax correctlyand is right, just by the simplicity of his answer.

And also, since we've hijacked the board today, and are doing more chatting than GMAT work, I'd like to note that I wonder how Paul is doing on his test...
SVP
SVP
User avatar
Joined: 30 Oct 2003
Posts: 1799
Location: NewJersey USA
Followers: 3

Kudos [?]: 29 [0], given: 0

GMAT Tests User
 [#permalink] New post 17 Jan 2004, 12:19
Hell yeah, I dont want these chats to contribute to my posts by more than 10% in numbers.
Paul will do good. He has been good.
Intern
Intern
User avatar
Joined: 01 Dec 2003
Posts: 35
Location: infront of my LCD
Followers: 0

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

 [#permalink] New post 17 Jan 2004, 15:20
Cool!

Anyone come up with a better way to solve it?

The thinking didnt take that long, just the work of solving for A,B,C
Senior Manager
Senior Manager
Joined: 11 Nov 2003
Posts: 356
Location: Illinois
Followers: 1

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

GMAT Tests User
 [#permalink] New post 20 Jan 2004, 13:35
anandnk wrote:
(A+B) + (B+C) + (C+A) = 6/5+3/2+2 = 47/10
In this time 3 times work is done
2A+2B+2C will do one job in 47/30 hours
so
A+B+C will need 47/60 hrs to do one job, working together

Thus they need 47 minutes to complete one job.


Hey Anand,

I do not see any difference between yours and calnhob's way of interpreting this problem.

Looking at your logic, I believe that you also considered that

A and B together took 6/5 hours to complete the ENTIRE job.
B and C together took 3/2 hours to complete the ENTIRE job.
A and C together took 2 hours to complete the ENTIRE job.

This is the same way in which calnhob interpreted the problem. But I think he applied the right formula.

So your statement "In 47/10 hours the work is completed 3 times is correct" (If each pair works once and finishes the entire job)

However, I think it is not correct to say that

If 2A + 2B + 2C can complete 3 times a job in 47/10 minutes, it will take 47/30 minutes to complete the job once. The proportionality can not be applied here because everybody has different rate of working. Here the effeciency factor comes in to play. (consider a simple example where all the players work with a different rates and it will be more clear)

In my opinion, the work related problems can not be solved by applying the straight formula. Because the longer one takes to finish a job, he lesser is the amount of work that can be finished in unit time.
  [#permalink] 20 Jan 2004, 13:35
    Similar topics Author Replies Last post
Similar
Topics:
Popular new posts If A and B work together, they will complete a job in 7.5 GMATT73 10 29 Oct 2005, 09:19
New posts working together at their constant rates , A and B can fill arjtryarjtry 6 18 Jul 2008, 05:08
New posts Working together at their respective rates, machine A, B, arjtryarjtry 3 22 Jul 2008, 10:46
Popular new posts 9 Experts publish their posts in the topic Working together, printer A and printer B would finish the gauravnagpal 12 01 Sep 2010, 10:12
This topic is locked, you cannot edit posts or make further replies. New 4 Experts publish their posts in the topic If A, B & C can build a wall in 4 hours,working together, innocous 12 02 Sep 2013, 11:39
Display posts from previous: Sort by

for a certain job,A and B together worked for 6/5 hours, B

  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®.