SOLUTION: A contractor undertook to build a road in 200 days he employed 140 men after 60 days he found that only one fourth of the road could be built how many additional Men should be em

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Question 1112556: A contractor undertook to build a road in 200 days he employed 140 men after 60 days he found that only one fourth of the road could be built
how many additional Men should be employed to complete the work in time

Found 4 solutions by josgarithmetic, josmiceli, ikleyn, MathTherapy:
Answer by josgarithmetic(39613) About Me  (Show Source):
You can put this solution on YOUR website!
r, the rate of working for 1 worker
n, the additional workers needed
140, the number of days that all the workers including the additional n need to finish the job

system%28%28140r%29%2A60=1%2F4%2C%28140%2Bn%29r%2A140=3%2F4%29
.
.
n=%283%2F4%29%281%2F140%29%281%2Fr%29-140

n=%283%2F4%29%281%2F140%29%2A4%2A140%2A60-140
n=3%2A60-140
n=180-140
highlight%28n=40%29

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The contractor figures that:
For +140+ men, their rate of working would be:
+%281%2F4%29+%2F+200+=+1%2F800+ jobs/days
One man would work +140+ times slower than this, or
+1%2F112000+ jobs/days
--------------------------
In +60+ days, the +140+ men completed:
+%28+1%2F800+%29%2A60+=+3%2F40+ of the job, so
there is +37%2F40+ left to do in +200+-+60+=+140+ days
--------------------------
Let +x+ = number of men needed to finish
the job in +140+ days
--------------------------
+x%2A%28+1%2F112000+%29+=+%28%28+37%2F40+%29%29+%2F+140+
+x+=+%28+37%2A112000+%29+%2F+%28+40%2A140+%29+
+x+=+4144000+%2F+5600+
+x+=+740+
+740+-+140+=+600+
He needs to hire 600 more men to finish on time
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Definitely get a 2nd opinion on this if you have the
time. If you know what the answer should be, don't bother

Answer by ikleyn(52752) About Me  (Show Source):
You can put this solution on YOUR website!
.
You just have two solutions.

The solution by @josmiceli is incorrect.

The solution by @josgarithmetic is correct.


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@MathTherapy, I agree with you in that every solution by @josgarithmetic must be re-written, replaced and substituted
until this person will leave the forum.



Answer by MathTherapy(10549) About Me  (Show Source):
You can put this solution on YOUR website!
A contractor undertook to build a road in 200 days he employed 140 men after 60 days he found that only one fourth of the road could be built
how many additional Men should be employed to complete the work in time
The 140 men, in the 60 days, worked at a rate of 33,600 "man-days"

With ¼ of job completed, ¾ remains to be completed in 140 (200 – 60) days
At the same rate (33,600 "man-days"), and with number of additional men being A, we get:
matrix%281%2C3%2C+140+%2B+A%2C+%22=%22%2C+%2233%2C600%22%283%2F4%29%2F140%29_____________
140 + A = 60(3)
A, or additional number of men needed to complete job =
Joscemeli, you're WAY, WAY off!!
Based on your answer, and with that number of additional men, for a total of 740,
it sounds more like building a skyscraper, a toll-bridge, or the railroad, I guess!