SOLUTION: Please help !
It takes Ralph 14 hours to paint a fence alone. Lisa can do the same job in 17 hours. If Ralph paints alone for 45 minutes before Lisa begins helping, how long must
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Question 951384: Please help !
It takes Ralph 14 hours to paint a fence alone. Lisa can do the same job in 17 hours. If Ralph paints alone for 45 minutes before Lisa begins helping, how long must they work together to finish painting the fence? Give your answer as a simplified fraction.
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
How much of the fence does Ralph paint in min ?
hrs
Ralph's rate of painting is:
( 1 fence ) / ( 14 hrs )
----------------------
( Ralph's rate ) x ( time spent painting ) = ( fraction of fence painted )
That means there is of the fence left to paint
----------------------
Add their rates of working to get rate working together
L:et = their time in hrs to paint the remaining
of the fence
----------------------
Multiply both sides by
hrs
Strange result. Get another opinion. I may have
answered this twice. If so, sorry. I really think
my method is OK, though
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