SOLUTION: A contractor was engaged to finish 6km of railway line in 210 days; but after employing 120 men for 50 days he found that only 1.2km of line was completed. How many additional men

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Question 889078: A contractor was engaged to finish 6km of railway line in 210 days; but after employing 120 men for 50 days he found that only 1.2km of line was completed. How many additional men must be engaged so that the work is completed within the given time.
Answer by josgarithmetic(39625) About Me  (Show Source):
You can put this solution on YOUR website!
What Happened: 120 men worked at each individual rate of r km per day for 50 days, finishing 1.2 km of railway.
RT=J
120%2Ar%2A50=1.2 and notice this is not in units of "JOBS" but only in units of kilometers of rail track on the right, and kilometers per day and number of days on the left member. The value for r can be found.

r=1.2%2F%28120%2A50%29
r=1%2F%28100%2A50%29
highlight%28r=1%2F5000%29 kilometer/day for 1 man

Let n = how many additional men to add so that the remaining assigned unfinished railway can be done in the remaining expected days.

%28n%2B120%29%2Ar%2A%28210-50%29=6-1.2
highlight%28%28n%2B120%29%281%2F5000%29%28210-50%29=6-1.2%29
I left this unfinished so you see what is happening with the numbers. Solve for n.