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

It is currently 31 Jan 2015, 00:35

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

A, B and C can do a work in 6, 8, 12 days resp. B and C work

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
TAGS:
Director
Director
avatar
Joined: 24 Oct 2005
Posts: 660
Location: London
Followers: 1

Kudos [?]: 7 [0], given: 0

A, B and C can do a work in 6, 8, 12 days resp. B and C work [#permalink] New post 04 May 2006, 07:10
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
A, B and C can do a work in 6, 8, 12 days resp. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?
Manager
Manager
User avatar
Joined: 27 Jan 2006
Posts: 156
Location: Europe
Followers: 1

Kudos [?]: 2 [0], given: 0

Re: PS Work [#permalink] New post 04 May 2006, 07:57
remgeo wrote:
A, B and C can do a work in 6, 8, 12 days resp. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?


Working spd per day.
a) 1/6
b) 1/8
c) 1/12

when b, c work together, their working speed is 1/8 + 1/12 = 20/96
because they worked for 2 days, 20/96 * 2 = 5/12

the left amount of work is 1-5/12=7/12

when a and c work together, spd is 1/6+1/12 = 1/4

(7/12) / (1/4) = 7/3
Manager
Manager
avatar
Joined: 29 Apr 2006
Posts: 85
Followers: 1

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

 [#permalink] New post 04 May 2006, 08:04
4 days. This is based on A&B working for 2 consecutive days following the 2 days that B&c worked.
Work done by B&C = 2(B+C) = 2(1/8 + 1/12) = 5/12
Work done by A+B for 2 days = 2(A+B) = 2(1/6 +1/8) = 7/12

Total work = 5/12 +7/12 =1
Total days = 2 +2 = 4
Manager
Manager
avatar
Joined: 29 Apr 2006
Posts: 85
Followers: 1

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

Re: PS Work [#permalink] New post 04 May 2006, 08:10
Question says that A takes the place of C. There we have the work done by A+B.

jeunesis wrote:
remgeo wrote:
A, B and C can do a work in 6, 8, 12 days resp. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?


Working spd per day.
a) 1/6
b) 1/8
c) 1/12

when b, c work together, their working speed is 1/8 + 1/12 = 20/96
because they worked for 2 days, 20/96 * 2 = 5/12

the left amount of work is 1-5/12=7/12

when a and c work together, spd is 1/6+1/12 = 1/4

(7/12) / (1/4) = 7/3
VP
VP
User avatar
Joined: 29 Dec 2005
Posts: 1349
Followers: 7

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

Re: PS Work [#permalink] New post 04 May 2006, 08:15
remgeo wrote:
A, B and C can do a work in 6, 8, 12 days resp. B and C work together for 2 days and then A takes C's place. How long will it take to finish the work?

remaining work after 2 days of work by a and b = 1-2(1/12+1/8)=7/12
a and b can do 7/12 work in 2 days = (24/7)(7/12) = 2 days

so total days = 4 days
Manager
Manager
avatar
Joined: 13 Apr 2006
Posts: 56
Followers: 0

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

 [#permalink] New post 04 May 2006, 08:40
to get amount finished in 2 days w/B & C: (1/8 + 1/12)*2=5/12

subtract from 1
i.e. 12/12 - 5/12 = 7/12

7/12 = (1/6*1/8)t
t=2

total days= 2 + 2=4
Manager
Manager
User avatar
Joined: 27 Jan 2006
Posts: 156
Location: Europe
Followers: 1

Kudos [?]: 2 [0], given: 0

 [#permalink] New post 04 May 2006, 08:53
i did silly mistake. :oops:
GMAT Club Legend
GMAT Club Legend
User avatar
Joined: 07 Jul 2004
Posts: 5079
Location: Singapore
Followers: 20

Kudos [?]: 173 [0], given: 0

 [#permalink] New post 05 May 2006, 02:00
A = 1/6 job per day
B = 1/8 job per day
C = 1/12 job per day

B+C = 1/8 + 1/12 = 5/24 job per day. They work for two days, so 7/12 job is left.

A+B = 1/6 + 1/8 = 7/24 job per day. The # of days to complete = 7/12 * 24/7 = 2 days.

Total = 2+2 = 4 days
Senior Manager
Senior Manager
avatar
Joined: 29 Jun 2005
Posts: 403
Followers: 1

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

 [#permalink] New post 05 May 2006, 03:09
Yes it is 4

A=w/6, B=w/8, C=w/12
B+C for 2 days = (w/8+w/12)*2=5w/12, so 7w/12 remains
A takes C place, thus (w/8+w/6)*x=7w/12  x=2
2+2=4
Answer 4 days
  [#permalink] 05 May 2006, 03:09
    Similar topics Author Replies Last post
Similar
Topics:
3 Experts publish their posts in the topic Three men A, B and C working together can do a work in 30 da abhishekkhosla 8 20 Oct 2013, 12:42
A and B together can do a peace of work in 12 days,which B sravan_m444 13 05 Feb 2007, 10:30
2 women A and B can mow a field in 8 an 12 hrs resp. They remgeo 8 04 May 2006, 07:31
Working together, A and B can do a job in 6 days. B and C GMATT73 6 29 Oct 2005, 09:21
Working together A and B can do a job in 6 days. B & C gmacvik 6 26 Sep 2005, 18:36
Display posts from previous: Sort by

A, B and C can do a work in 6, 8, 12 days resp. B and C work

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

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®.