SOLUTION: It takes 7 people 12 hours to complete a job. If they worked at the same rate, how many people would it take to complete the job in 16 hours.

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Question 631704: It takes 7 people 12 hours to complete a job. If they worked at the same rate, how many people would it take to complete the job in 16 hours.
Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!
It takes 7 people 12 hours to complete a job. If they worked at the same rate,
how many people would it take to complete the job in 16 hours.

Use the job-worker-time formula, which is:

%28W%5B1%5DT%5B1%5D%29%2FJ%5B1%5D%22%22=%22%22%28W%5B2%5DT%5B2%5D%29%2FJ%5B2%5D

where

W1 = the number of workers in the first situation.
T1 = the number of time units (days in this case) in the first situation.
J1 = the number of jobs in the first situation.

W2 = the number of workers in the second situation.
T2 = the number of time units (days in this case) in the second situation.
J2 = the number of jobs in the second situation.

W1 = 7            W2 = the unknown quantity     
T1 = 12            T2 = 16 
J1 = 1             J2 = 1

[There was only 1 job, so the number of jobs in both situations is 1.



%28W%5B1%5DT%5B1%5D%29%2FJ%5B1%5D%22%22=%22%22%28W%5B2%5DT%5B2%5D%29%2FJ%5B2%5D

%287%2A12%29%2F1%22%22=%22%22%28W%5B2%5D%2A16%29%2F1

      84 = 16W2
      
Divide both sides by 8

      84%2F16 = W2

      21%2F4 = W2

The answer would be 5%261%2F4 workers. But since it's not nice to
cut workers in fourths :), we have to use 6 workers. and get it
done in less than 16 hours.

Edwin