SOLUTION: Mutt and Jeff need to paint a fence. Mutt can do the job alone 6 hours faster than Jeff. If together they work for 10 hours and finish only 4/5 of the job, how long would Jeff nee

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Mutt and Jeff need to paint a fence. Mutt can do the job alone 6 hours faster than Jeff. If together they work for 10 hours and finish only 4/5 of the job, how long would Jeff nee      Log On


   



Question 666681: Mutt and Jeff need to paint a fence. Mutt can do the job alone 6 hours faster than Jeff. If together they work for 10 hours and finish only 4/5 of the job, how long would Jeff need to do the job alone?
Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!


If it takes 10 hours for the pair to complete of the job, then it takes hours to complete the whole job, and therefore the pair working together can complete of the job in 1 hour. Let represent the time it takes Jeff to do the whole job. Then is the time it takes Mutt to do the whole job. Then Jeff can do of the job in one hour and Mutt can do of the job in one hour. Now we can say that:



Solve for . Once you have it reduced to a quadratic in standard form, it will not factor. Use the quadratic formula. One of the roots will be less than 6, so discard that answer -- Mutt can't paint the fence in negative time, can he?

John

My calculator said it, I believe it, that settles it
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