Question

ram works 8 days shyam and ghansyam his work 12 days solve this

Answer 1

 GMAT Club  



HOME

NEW POSTS

FORUM

TESTS

DEALS & DISCOUNTS

REVIEWS

CHAT

TERMS AND CONDITIONS AND PRIVACY POLICY

   GMAT Club Rules

Login

Register Forgot password?

Close

Close

GMAT Club Forum Index

Ram can do a piece of work in 8 days which syam can finsih : Quant Question Archive [LOCKED]

Topic Discussion

Page 1 of 1

sravan_m444

Feb 5, 2007

Ram can do a piece of work in 8 days which syam can finsih in 12 days.If they work at it on alternate days,with Ram begining,in how many days,the work will be finished?

--== Message from GMAT Club Team ==--

This is not a quality discussion. It has been retired. 

If you would like to discuss this question please re-post it in the respective forum. Thank you!

To review the GMAT Club's Forums Posting Guidelines, please follow these links: Quantitative | Verbal Please note - we may remove posts that do not follow our posting guidelines. Thank you.

 Kudos

 

devilmirror

Feb 5, 2007

sravan_m444 wrote:Ram can do a piece of work in 8 days which syam can finsih in 12 days.If they work at it on alternate days,with Ram begining,in how many days,the work will be finished?



Ram's Work Rate = R = 1/8 (work/day) 
Syam's Work Rate = S = 1/12 (work/day) 

Before the job is done, if Ram work n days, Syam will also works n days. 
Therefore, work done by Ram = n/8 work 
work done by Syam = n/12 

As mentioned above that both work is not done, we can write this statement 
n/8 + n/12 <= 1 
n* ((3+2)/24) <= 1 
n <= 24/5 
n <= 4.8 days 
This means that Ram and Syam will have to work at least 4 days each before the job can be done. 
Work from Ram = 4 * 1/8 = 1/2 
Work from Syam = 4 * 1/12 = 1/3 
Total = 1/2 + 1/3 = 5/6 
On 8th day, the job remain 1 - 5/6 = 1/6 work 
On 9th day, Ram will work on this day and the job remain = 1/6 - 1/8 = 1/24. 
On the 10th day, Syam will do the rest and the job is done. 

Therefore, it will take 10 days to finish the job.

 Kudos

 

devilmirror

Feb 5, 2007

Here is another approach for this question. 

R = 1/8 (work/day) 
S = 1/12 (work/day) 

If they work together, their work rate = (1/8 + 1/12) = 5/24 (work/day) 

They will need 24/5 (day/work) = 4.8 days to finish one work. 

But since Ram and Syam will work on alternate day they will need total of 4.8 x 2 = 9.6 days = 10 days to finish the work.

 Kudos

 0 kudos, 1 bookmark

ggarr

Feb 5, 2007

Ram can do a piece of work in 8 days which syam can finsih in 12 days.If they work at it on alternate days,with Ram begining,in how many days,the work will be finished?

Ram 
rt = w 
r(8) = 1 
r= 1/8 

Syam 
rt = w 
r(12) = 1 
r=1/2 

1/8 + 1/12 = 5/24 

5/24(x) = 1 
****remember, 5/24 is really 1/8 + 1/12, in other words, 2 days**** 
x = 4.8 
4.8*2 = 9.6 = 10 days

 Kudos

 

amorpheus

Feb 5, 2007

R can do 1/8 of the job in 1 day 
S can do 1/12 off the job in 1 day 

If R and S both worked together for a day they can finish (1/8 + 1/12) of the job 

meaning 5/24 of the job can be done in 1 day 
Therefore to do 1 jobit will take 24/5 days = 4.8 days 

Since both are working alternate days it will take twice as long, meaning 2(4.8) days = 9.6 = 10 days.