SOLUTION: ADE can do a certain job in 3hours, OBI can do the same job in 5hours, and AUDU can do the same job in 7hours. How long would the job take with all three working together?
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-> SOLUTION: ADE can do a certain job in 3hours, OBI can do the same job in 5hours, and AUDU can do the same job in 7hours. How long would the job take with all three working together?
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Question 1070380: ADE can do a certain job in 3hours, OBI can do the same job in 5hours, and AUDU can do the same job in 7hours. How long would the job take with all three working together? Found 2 solutions by Edwin McCravy, ikleyn:Answer by Edwin McCravy(20054) (Show Source):
You can put this solution on YOUR website! ADE can do a certain job in 3hours, OBI can do the same job in 5hours, and AUDU can do the same job in 7hours. How long would the job take with all three working together?
ADE's working rate is 1 job per 3 hours or 1/3 jobs per hour.
OBI's working rate is 1 job per 5 hours or 1/5 jobs per hour.
AUDU's working rate is 1 job per 7 hours or 1/7 jobs per hour.
So together in one hour they can 1/3 + 1/5 + 1/7 = 71/150 of a job.
That's 71 jobs in 150 hours or 1 job in 150/71 = 1.5 hours, rounded off.
Edwin
