GMAT Question of the Day - Daily to your Mailbox; hard ones only

It is currently 11 Dec 2018, 03:26

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 in December
PrevNext
SuMoTuWeThFrSa
2526272829301
2345678
9101112131415
16171819202122
23242526272829
303112345
Open Detailed Calendar
  • Free GMAT Prep Hour

     December 11, 2018

     December 11, 2018

     09:00 PM EST

     10:00 PM EST

    Strategies and techniques for approaching featured GMAT topics. December 11 at 9 PM EST.
  • The winning strategy for 700+ on the GMAT

     December 13, 2018

     December 13, 2018

     08:00 AM PST

     09:00 AM PST

    What people who reach the high 700's do differently? We're going to share insights, tips and strategies from data we collected on over 50,000 students who used examPAL.

Mary and Jane working together can complete a task in 2 hours and 24 m

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

Hide Tags

MBA Section Director
User avatar
V
Affiliations: GMATClub
Joined: 22 May 2017
Posts: 1372
Concentration: Nonprofit
GPA: 4
WE: Engineering (Computer Software)
Mary and Jane working together can complete a task in 2 hours and 24 m  [#permalink]

Show Tags

New post 01 Dec 2018, 09:27
00:00
A
B
C
D
E

Difficulty:

  75% (hard)

Question Stats:

53% (02:43) correct 47% (02:27) wrong based on 57 sessions

HideShow timer Statistics

GMATbuster's Weekly Quant Quiz#11 Ques #10


For Questions from earlier quizzes: Click Here


Mary and Jane working together can complete a task in 2 hours and 24 minutes. Jane and Karen working together can complete the same task in 1 hour 20 minutes whereas Karen and Mary working together can complete the task in 1 hour 30 minutes. Which of the following best represents the time (in minutes) taken to complete the task if Mary, Jane and Karen work together?

A)42
B)48
C)54
D)60
E)66

_________________

New project wSTAT(which Schools To Apply To?)

GMATClub School Ambassador

B-School app with GRE

New - RC Butler - 2 RC's everyday

Intern
Intern
avatar
B
Joined: 11 Apr 2017
Posts: 15
Re: Mary and Jane working together can complete a task in 2 hours and 24 m  [#permalink]

Show Tags

New post 01 Dec 2018, 10:06
workout wrote:

GMATbuster's Weekly Quant Quiz#11 Ques #10


For Questions from earlier quizzes: Click Here


Mary and Jane working together can complete a task in 2 hours and 24 minutes. Jane and Karen working together can complete the same task in 1 hour 20 minutes whereas Karen and Mary working together can complete the task in 1 hour 30 minutes. Which of the following best represents the time (in minutes) taken to complete the task if Mary, Jane and Karen work together?

A)42
B)48
C)54
D)60
E)66

IMO-D


Sent from my iPhone using GMAT Club Forum mobile app
Intern
Intern
avatar
B
Joined: 07 Jun 2018
Posts: 11
GMAT ToolKit User CAT Tests
Mary and Jane working together can complete a task in 2 hours and 24 m  [#permalink]

Show Tags

New post Updated on: 03 Dec 2018, 06:40
m+j = 5/12---------------1( work done by m and j in 1 hr )
j + k= 3/4------------------2 ( work done in 1 hr )
k+m = 2/3----------------3( work done in 1 hr)

add eq 1,2 3
2 ( j+ K+ m) = 5/12 + 3/4 + 2/3
j+k+M = 22/12 * 1/2 = 11/12 ( the total work done by j, k, m in 1 hr)

Now we are left with 1/12 of work
1- (11/12) = 1/12
Approx 1/12 work is done in 6 mins
So 60 min + 6 = 66 min

E is correct

Originally posted by harshsaini on 01 Dec 2018, 10:55.
Last edited by harshsaini on 03 Dec 2018, 06:40, edited 1 time in total.
Manager
Manager
avatar
B
Joined: 29 May 2017
Posts: 127
Location: Pakistan
Concentration: Social Entrepreneurship, Sustainability
Re: Mary and Jane working together can complete a task in 2 hours and 24 m  [#permalink]

Show Tags

New post 02 Dec 2018, 21:20
workout wrote:

GMATbuster's Weekly Quant Quiz#11 Ques #10


For Questions from earlier quizzes: Click Here


Mary and Jane working together can complete a task in 2 hours and 24 minutes. Jane and Karen working together can complete the same task in 1 hour 20 minutes whereas Karen and Mary working together can complete the task in 1 hour 30 minutes. Which of the following best represents the time (in minutes) taken to complete the task if Mary, Jane and Karen work together?

A)42
B)48
C)54
D)60
E)66

m+j= 144
j+k=80
k+m=90

adding gives:

2m + 2j + 2k = 314
m+j+k= 157

Can you explain where i am going wrong?
Intern
Intern
avatar
B
Joined: 27 Sep 2017
Posts: 8
CAT Tests
Re: Mary and Jane working together can complete a task in 2 hours and 24 m  [#permalink]

Show Tags

New post 04 Dec 2018, 12:09
1
Mansoor50 wrote:
workout wrote:

GMATbuster's Weekly Quant Quiz#11 Ques #10


For Questions from earlier quizzes: Click Here


Mary and Jane working together can complete a task in 2 hours and 24 minutes. Jane and Karen working together can complete the same task in 1 hour 20 minutes whereas Karen and Mary working together can complete the task in 1 hour 30 minutes. Which of the following best represents the time (in minutes) taken to complete the task if Mary, Jane and Karen work together?

A)42
B)48
C)54
D)60
E)66

m+j= 144
j+k=80
k+m=90

adding gives:

2m + 2j + 2k = 314
m+j+k= 157

Can you explain where i am going wrong?

In this type of approach consider work done to be the LCM of three values



M+J= 144min
J+K=80 min
K+M= 90min



consider total work done to be 144

SO,

rate of M+J = 1 SINCE rate = work/time

rate of J+K = 1.8

rate of K+M =1.6



total rate equation will be

(M+J)+(J+K)+(K+M) = 1+1.8+1.6

2 ( M+J+K) = 4.4

(M+J+K) = 2.2


TOTAL WORK DONE = TOTAL RATE * TOTAL TIME


144 /2.2 = 65.45 approx 66 min




please let me know if i went wrong , if not, do consider kudos!
GMAT Club Bot
Re: Mary and Jane working together can complete a task in 2 hours and 24 m &nbs [#permalink] 04 Dec 2018, 12:09
Display posts from previous: Sort by

Mary and Jane working together can complete a task in 2 hours and 24 m

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


Copyright

GMAT Club MBA Forum Home| About| Terms and Conditions and Privacy Policy| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne

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®.