<PRE><B>Question 933869</B>
A contract is to be completed in 46 days and 117 men were set to work, each working 8 hours a day.
 After 33 days 4/7 of the work is completed.
Find how many man-hrs expended to complete 4/7 of the job?
117*8*33 = 30888 man-hrs
let t = total man-hrs required for the job
{{{4/7}}}t = 30888
t = 54054 man hrs
:
 How many additional men may be employed so that the work be completed in time, each man now working 9 hours a day? 
The remaining 3/7 of the work required: {{{3/7}}}*54054 = 23166 man-hrs
let m = no. men working 9 hrs a day to finish the job in 13 days (46-33)
m*9*13 = 23166
117m = 23166
m = 198 men total
then
198-117 = 81 more men required
:
:
See of that adds up
117*8*33 = 30888 man-hrs for the first 33 days
198*9*13 = 23166 man-hrs for the last 13 days
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total man-hrs: 54054 man-hrs

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