SOLUTION: Printing Press A starts working on a job at 8:00 am. Working alone, press A would take 24 hours to do the job. At 9:30 am, press B also begins to run the same job as A. Press B is
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-> SOLUTION: Printing Press A starts working on a job at 8:00 am. Working alone, press A would take 24 hours to do the job. At 9:30 am, press B also begins to run the same job as A. Press B is
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Question 621276: Printing Press A starts working on a job at 8:00 am. Working alone, press A would take 24 hours to do the job. At 9:30 am, press B also begins to run the same job as A. Press B is twice as fast as press A. What time will the job be completed? Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! How much of the job did press A get done in 1.5 hrs
from 8 AM to 9:30 AM?
A's rate is ( 1 job ) / ( 24 hrs )
In 1.5 hrs: job/hr
Now both A and B work on job
There is
of the job left to do.
B's rate is ( 1 job ) / ( 12 hrs )
Multiply both sides by
In 7.5 hrs after B starts, the job is done
9:30 + 7.5 = 5 PM job is done
check answer:
OK