SOLUTION: johnny can do a job in 6 hours. jeffrey can do the same job in 9 hours. how long would it take them to do the job together?

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Question 863871: johnny can do a job in 6 hours. jeffrey can do the same job in 9 hours. how long would it take them to do the job together?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Let x represent time together

+1%2F6+%2B+1%2F9+=+1%2Fx    |Multiplying thru by 18x so as all denominators = 1

 3x  + 2x = 18

    5x = 18

     x = 3.6 hrs