- Hey all !What is the correct method and answer ?There are 3 explanation below with 3 different answers as - 30days, 7.5 days and 15 days ?Can you all 3 - Rahul , ashish anand and raja raman - explain which is correct answer and why ?ThanksAnurag

On 4/22/10,**Rahul R. Gupta**<rrahulanker@...> wrote:To neeli

1/a+1/b+1/c = 1/15 eqn 1

for 5 days work done = 5/15 = 1/3

work remaining = 1-1/3 = 2/3

2/3 of work has done by b + c in 20 day then

ful work will be done by them in 20*3/2 =30 day

1/b+1/c = 1/30 eqn 2

from eqn 1 & 2

1/a+1/30 = 1/15

1/a = 1/15

there fore "a" alone can complete same work in 15 days

--- On**Mon, 19/4/10, Neeli**wrote:*<neeli2101@...>*

From: Neeli <neeli2101@...>

Subject: [2IIM CAT Prep] Work....

To: ascent4cat@yahoogroups.com

Date: Monday, 19 April, 2010, 5:43 PMHI,

My concepts in Work are weak.Need Help.

Please provide elaborated answer for the following problem so that I can refer the same approach in other questions as well....

A,B and C can do a job in 15 days.After working with B and C for 5 days,A leaves.Then B and C finish it in 20 days more.In how many days can A do the job alone?

Thanks in advance.

Neelima

- ABC together finish in 15 days.

after 5 days 1/3rd work is over.

The remaining 2/3rd work B, C finish in 20 days.

So B and C together can finish the entire work in 30 days.

But together with A they can do in 15 days.

So A is as good as B and C together.

So A alone takes 30 days to finish the job.

--- In ascent4cat@yahoogroups.com, Divik Gupta <divik.gupta@...> wrote:

>

> suppose

> A does a unit work per day

> B does b unit work per day

> C does c unit wrk per day

>

> Total work = 15a+ 15b+15c

> Work done in 5 days= 5a+5b+5c

> Work left= 10a+10b+10c

> This work is done by B and C in 20days

> so 10a+10b+10c=20b+20c

> => a=b+c

> so total work 15(a+b+c)=15(2a)=30a

>

> so ans is 30 days

>

>

>

> On Sat, May 1, 2010 at 6:33 PM, anurag gupta <anurag.sotr@...> wrote:

>

> >

> >

> > Hey all !

> >

> > What is the correct method and answer ?

> >

> > There are 3 explanation below with 3 different answers as - 30days, 7.5

> > days and 15 days ?

> >

> > Can you all 3 - Rahul , ashish anand and raja raman - explain which is

> > correct answer and why ?

> >

> > Thanks

> > Anurag

> >

> >

> > On 4/22/10, Rahul R. Gupta <rrahulanker@...> wrote:

> >>

> >>

> >>

> >> To neeli

> >>

> >> 1/a+1/b+1/c = 1/15 eqn 1

> >> for 5 days work done = 5/15 = 1/3

> >> work remaining = 1-1/3 = 2/3

> >> 2/3 of work has done by b + c in 20 day then

> >> ful work will be done by them in 20*3/2 =30 day

> >> 1/b+1/c = 1/30 eqn 2

> >>

> >> from eqn 1 & 2

> >> 1/a+1/30 = 1/15

> >> 1/a = 1/15

> >>

> >> there fore "a" alone can complete same work in 15 days

> >>

> >> --- On *Mon, 19/4/10, Neeli <neeli2101@...>* wrote:

> >>

> >>

> >> From: Neeli <neeli2101@...>

> >> Subject: [2IIM CAT Prep] Work....

> >> To: ascent4cat@yahoogroups.com

> >> Date: Monday, 19 April, 2010, 5:43 PM

> >>

> >>

> >>

> >> HI,

> >> My concepts in Work are weak.Need Help.

> >> Please provide elaborated answer for the following problem so that I can

> >> refer the same approach in other questions as well....

> >>

> >> A,B and C can do a job in 15 days.After working with B and C for 5 days,A

> >> leaves.Then B and C finish it in 20 days more.In how many days can A do the

> >> job alone?

> >>

> >> Thanks in advance.

> >> Neelima

> >>

> >>

> >>

> >

> >

>