SOLUTION: How do you solve a person-day problem? For example, "one man works 55 days to finish a job. How long will it take 5 men to do the same job all working at equal rates of speed?"

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Question 827945: How do you solve a person-day problem? For example, "one man works 55 days to finish a job. How long will it take 5 men to do the same job all working at equal rates of speed?"
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Rate*Time=Output
Let the work be done when the output reaches 1.
.
.
One man's rate is
R1%2A55=1
R1=1%2F55
Five men's rate would then be 5 times as much.
R2=5%2A%281%2F55%29
R2=5%2F55=1%2F11
So then,
R2%2AT2=1
%281%2F11%29%2AT2=1
T2=11
So it takes 5 men only 11 days to do the same job.