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Old Monday, September 14, 2015
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RMKamran RMKamran is offline
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Quote:
Originally Posted by Mashaaal View Post
my answer is 7.5 (approx 8 because 8 is not in the options)
the number of men and boys is increasing so they will be doing the work in less days, therefore men and boys are at inverse with days (so it is indirect proportion)
Yup, I have a test tomorrow. I have done with the other part of mathematics but stuck in this weird question

8 is among the options. Btw, I know that it's indirect proportion but it's really confusing and I think this question is solved by a linear equation. Let's see if somebody else knows it.

Quote:
Originally Posted by FAHEEM ULLAH KHAN MAHSUD View Post
Ans: Given, work can be done by:
3*20 = 60 man-days
or
6*20 = 120 boy-days
therefore
60 md = 120 b.d

divide by 60
md = 2bd
:
how many days will 6 men and 8 boys take to do the same work?
let d = no. days to accomplish this in terms of man-days
we know that 8bd = 4 md; therefore
6d + 4d = 60
10d = 60
d = 6 days for 6 men and 8 boys to do the job
Jazak'ALLAH khairan.

Thanks a bunch bro but I didn't understand the 2nd part of your solution. Could you please throw some light on this: we know that 8bd = 4 md; therefore
6d + 4d = 60
10d = 60
d = 6 days for 6 men and 8 boys to do the job

How did you get 4md and where is 8bd after that step ?
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Last edited by Man Jaanbazam; Tuesday, September 15, 2015 at 12:22 AM. Reason: merge chain posts
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