Question 394478
A piece of work can be done in 48 days by 40 men.
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Each day 1/48 th of the job was done by 40 men
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Each man did (1/(48*40)th  = 1/1920th of the job.
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After 15 days, 16 men were transferred. 
In 15 days 15/1920 th of the job was done.
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There still remained 1905/1920 th of the job to be done.
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In how many days can the remaining men finish the work?
There are now 24 men working.
Each day 24/1020 th of the job is done
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# of days required is (amt of work to do)/(amt of work done in a day by 24 men)
= [1905/1920]/[24/1020] = 1905/24 = 79.375 days
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Cheers,
Stan H.