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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,776

A contractor agrees to complete a work in 100 days. He engaged 140 men for the job and after doing the work for 60 days, he came to know that only half the work was completed. How many more men should he hire to finish the work in the agreed time?

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**mathsyperson****Moderator**- Registered: 2005-06-22
- Posts: 4,900

So, 140 men did half the work in 60 days, and the boss needs enough extra men to get the remaining work done in 40 days. So that means...[left for others]

Why did the vector cross the road?

It wanted to be normal.

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**MathsIsFun****Administrator**- Registered: 2005-01-21
- Posts: 7,608

Approximately this many:

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..." - Leon M. Lederman

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**tt****Member**- Registered: 2005-07-03
- Posts: 32

He should hire 70 more men to complete the work in agreed time.

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,776

Excellent! You are correct! Tell us how you did it!

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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**tt****Member**- Registered: 2005-07-03
- Posts: 32

The contractor needed 140 men X 60 days = 8400 man-days to do half the work. So he'll need 8400 more man-days to do the rest. He only has 40 days left, then he'll need 8400 man-days / 40 days = 210 men. He already has 140 men, so he has to hire 70 more men.

*Last edited by tt (2005-07-14 17:53:51)*

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