<PRE><B>Question 1154714</B>

Howard and Edward, working together, can complete a job in 12 hours.  Edward requires 18 hours to do this job alone.  Howard and Edward start the job.  After they worked for 4 hours, Howard left the job.  How many hours will Edward require to finish the job working alone?

Edward requires 18 hours to do this job alone.

He does 1/18 of job in 1 hour

Howard and Edward start the job they worked for 4 hours,

They can complete the job in 12 hours

So they can do 1/12 of the job in 1 hour
they worked for 4 hours
so they completed 4/12 of the job = 1/3 of the job

balance job = 1-1/3 = 2/3 of the job

Edward does 1/18 of job in 1 hour

for 1/3 of the job he will take (1/3)/(1/18) hours

(1/3) *18

6 hours

Edward will take 6 hours to complete the job



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