It is currently 28 Jun 2017, 10:58

Live Now:

Open Admission Chat with MBA Expert, Donna Bauman. (Kellogg MBA Graduate and Former UNC Adcom)


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.

Close

Request Expert Reply

Confirm Cancel

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Machine M, N, O working simultaneously Machine M can produce

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:

Hide Tags

3 KUDOS received
Senior Manager
Senior Manager
User avatar
Status: mba here i come!
Joined: 07 Aug 2011
Posts: 264
GMAT ToolKit User
Machine M, N, O working simultaneously Machine M can produce [#permalink]

Show Tags

New post 26 Aug 2011, 07:30
3
This post received
KUDOS
11
This post was
BOOKMARKED
00:00
A
B
C
D
E

Difficulty:

  65% (hard)

Question Stats:

63% (03:03) correct 37% (02:15) wrong based on 221 sessions

HideShow timer Statistics

Machine M, N, O working simultaneously Machine M can produce x units in 3/4 of the time it takes machine N to produce the same amount of units. Machine N can produce x units in 2/3 the time it takes machine O to produce that amount of units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?

A. 1/2
B. 1/3
C. 4/13
D. 8/29
E. 6/33


[Reveal] Spoiler: Solution
N produces x units in ‘t’
M produces x units in ¾ t
O produces x units in 3/2t

In 1 minute total units produced by M,N,O working together = 1/t + 4/3t + 2/3t = 3/t
Ratio of work done by N in 1 minute = (1/t) / (3/t) = 1/3
This ratio will be the same no matter how long M, N, O work together.
[Reveal] Spoiler: OA

_________________

press +1 Kudos to appreciate posts
Download Valuable Collection of Percentage Questions (PS/DS)

1 KUDOS received
Intern
Intern
avatar
Status: GMAT - A logic game! Enjoy it!!
Joined: 19 Apr 2011
Posts: 17
Re: machines m,n,o working simaltaneously [#permalink]

Show Tags

New post 26 Aug 2011, 07:47
1
This post received
KUDOS
MBAhereIcome wrote:
Machine M,N,O working simultaneously Machine M can produce x units in 3/4 of the time it takes machine N to produce the same amount of units. Machine N can produce x units in 2/3 the time it takes machine O to produce that amount of units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?

A. 1/2
B. 1/3
C. 4/13
D. 8/29
E. 6/33


[Reveal] Spoiler: Solution
N produces x units in ‘t’
M produces x units in ¾ t
O produces x units in 3/2t

In 1 minute total units produced by M,N,O working together = 1/t + 4/3t + 2/3t = 3/t
Ratio of work done by N in 1 minute = (1/t) / (3/t) = 1/3
This ratio will be the same no matter how long M, N, O work together.


Okieee..

Now ultimately the speed of every machine is given with respect to Mach O.
So lets assume the speed of O, say 12 hrs to make x units (assuming 6 because we can see we will need to divide by 3 and 4

Mach O makes x units in 12 hrs
So, Mach N = 2/3 of O = 2/3*12 = 8 hrs to make x units
and Mach M = 3/4 of N = 3/4*8 = 6 hrs to make x units

No they are running simultaneously. Lets see how much each mach makes in 1 hr
Mach O = x/12 units
Mach N = x/8 units
Mach M = x/6 units

In 1 hr, together they make - x/12+x/8+x/6 = 3x/8
So what ratio of this has Mach N made?

(x/8) / (3x/8) = 1/3

Ans: B=1/3
_________________

Happy Learning ! :D


Show Thanks to fellow members with Kudos its shows your appreciation and its free

1 KUDOS received
Manager
Manager
avatar
Joined: 21 Aug 2010
Posts: 188
Location: United States
GMAT 1: 700 Q49 V35
GMAT ToolKit User
Re: machines m,n,o working simaltaneously [#permalink]

Show Tags

New post 04 Oct 2011, 12:25
1
This post received
KUDOS
Work done by O = 1/O
Work Done by N = 1/N = 1/(2/3)O = 3/2O

Work done by M = 1/M = 1/(3/4)N = 1/(3/4)(3/2O) = 12 /6 O = 2 /O

Worn done y N = 1/O + 3/2 O + 2/O = 2 + 3 + 4 / 2O = 9 /2O
= 1/3 part of whole work done
_________________

-------------------------------------

Senior Manager
Senior Manager
User avatar
Joined: 11 May 2011
Posts: 361
Location: US
Re: machines m,n,o working simaltaneously [#permalink]

Show Tags

New post 04 Oct 2011, 12:38
@MBAhereIcome - Kudos to you for this excellent question.

Answer is B. Cheers!
_________________

-----------------------------------------------------------------------------------------
What you do TODAY is important because you're exchanging a day of your life for it!
-----------------------------------------------------------------------------------------

Intern
Intern
avatar
Joined: 06 Nov 2011
Posts: 37
Location: Germany
Concentration: Entrepreneurship, General Management
GMAT Date: 03-10-2012
GPA: 3
GMAT ToolKit User
Re: machines m,n,o working simaltaneously [#permalink]

Show Tags

New post 07 Mar 2012, 09:04
Let O --> T = 12 hours to finish the job
Let N --> \(N = \frac{2}{3}*T = 8\) hours the job
Let M --> \(M = \frac{3}{4}*\frac{2}{3} * T = 6\) hours to finish the job
Combine their rates: \(\frac{1}{6}+\frac{1}{8}+\frac{1}{12} = \frac{3}{8}\) Rate to finish one job together
We are looking for the fraction of N on the whole output.
Rate of N is \(\frac{1}{8}\), multiply it with the total time of all machines \(*\frac{8}{3} = \frac{1}{3}\)

Hope its correct. Took me 10 minutes :|
Expert Post
11 KUDOS received
Veritas Prep GMAT Instructor
User avatar
S
Joined: 16 Oct 2010
Posts: 7449
Location: Pune, India
Re: machines m,n,o working simaltaneously [#permalink]

Show Tags

New post 07 Mar 2012, 09:17
11
This post received
KUDOS
Expert's post
1
This post was
BOOKMARKED
MBAhereIcome wrote:
Machine M,N,O working simultaneously Machine M can produce x units in 3/4 of the time it takes machine N to produce the same amount of units. Machine N can produce x units in 2/3 the time it takes machine O to produce that amount of units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?

A. 1/2
B. 1/3
C. 4/13
D. 8/29
E. 6/33


Think in terms of ratios for a quick clean solution.
Time taken by M : time taken by N = 3:4
So speed of M : speed of N = 4:3
Similarly, speed of N:speed of O = 3:2
Speed of M: Speed of N : Speed of O = 4:3:2
So N will produce 3/(2+3+4) = 1/3rd of the output
_________________

Karishma
Veritas Prep | GMAT Instructor
My Blog

Get started with Veritas Prep GMAT On Demand for $199

Veritas Prep Reviews

Intern
Intern
avatar
Joined: 01 Dec 2010
Posts: 3
Re: machines m,n,o working simaltaneously [#permalink]

Show Tags

New post 11 Mar 2012, 17:26
I know we are supposed to say thank you by just pressing kudos but I must add here that your methods are very efficient.


VeritasPrepKarishma wrote:
MBAhereIcome wrote:
Machine M,N,O working simultaneously Machine M can produce x units in 3/4 of the time it takes machine N to produce the same amount of units. Machine N can produce x units in 2/3 the time it takes machine O to produce that amount of units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?

A. 1/2
B. 1/3
C. 4/13
D. 8/29
E. 6/33


Think in terms of ratios for a quick clean solution.
Time taken by M : time taken by N = 3:4
So speed of M : speed of N = 4:3
Similarly, speed of N:speed of O = 3:2
Speed of M: Speed of N : Speed of O = 4:3:2
So N will produce 3/(2+3+4) = 1/3rd of the output
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 16023
Premium Member
Re: Machine M, N, O working simultaneously Machine M can produce [#permalink]

Show Tags

New post 20 Sep 2013, 10:07
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Current Student
User avatar
Joined: 06 Sep 2013
Posts: 1997
Concentration: Finance
GMAT ToolKit User
Re: Machine M, N, O working simultaneously Machine M can produce [#permalink]

Show Tags

New post 14 Mar 2014, 13:59
I would go with smart numbers on this one. Say that N=4, M=3 and O = 6. Therefore all working together will finish x in 4/3 hour. Now in 4/3 hour N does 1/4 so (4/3)(1/4) = 1/3. B is the correct answer

Peace
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 16023
Premium Member
Re: Machine M, N, O working simultaneously Machine M can produce [#permalink]

Show Tags

New post 07 Apr 2015, 09:44
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 09 Sep 2013
Posts: 16023
Premium Member
Re: Machine M, N, O working simultaneously Machine M can produce [#permalink]

Show Tags

New post 14 Jan 2017, 14:43
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
_________________

GMAT Books | GMAT Club Tests | Best Prices on GMAT Courses | GMAT Mobile App | Math Resources | Verbal Resources

Director
Director
avatar
S
Joined: 07 Dec 2014
Posts: 713
Re: Machine M, N, O working simultaneously Machine M can produce [#permalink]

Show Tags

New post 23 Jan 2017, 17:09
Machine M, N, O working simultaneously Machine M can produce x units in 3/4 of the time it takes machine N to produce the same amount of units. Machine N can produce x units in 2/3 the time it takes machine O to produce that amount of units. If all three machines are working simultaneously, what fraction of the total output is produced by machine N?

A. 1/2
B. 1/3
C. 4/13
D. 8/29
E. 6/33

M,N,O respective times=t/2, 2t/3, t
M,N,O combined rates=2/t+3/2t+1/t=4.5/t
N's fraction of total output=(3/2t)/(4.5/t)=1/3
B
Re: Machine M, N, O working simultaneously Machine M can produce   [#permalink] 23 Jan 2017, 17:09
    Similar topics Author Replies Last post
Similar
Topics:
5 Experts publish their posts in the topic In a workshop 10 machines working simultaneously can finish a work of GMATinsight 6 17 May 2017, 13:56
3 Working simultaneously at their respective constant rates, machine A a snorkeler 1 02 Jun 2016, 20:13
20 Experts publish their posts in the topic Machines A and B, working simultaneously at their respective constant Bunuel 18 23 Dec 2016, 05:32
74 Experts publish their posts in the topic Machine A and Machine B can produce 1 widget in 3 hours work changhiskhan 16 10 Aug 2015, 17:46
21 Experts publish their posts in the topic Machine M can produce x units in 3/4 of the time it takes machine N to vscid 12 05 Feb 2017, 06:20
Display posts from previous: Sort by

Machine M, N, O working simultaneously Machine M can produce

  new topic post reply Question banks Downloads My Bookmarks Reviews Important topics  


GMAT Club MBA Forum Home| About| 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®.