SOLUTION: Jonathan can paint a room in 8 hrs. After painting for 2 hours, his brother, David joined him and together, they finished painting the room in 3 1/3hours. In how many hours will Da
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-> SOLUTION: Jonathan can paint a room in 8 hrs. After painting for 2 hours, his brother, David joined him and together, they finished painting the room in 3 1/3hours. In how many hours will Da
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Question 1021361: Jonathan can paint a room in 8 hrs. After painting for 2 hours, his brother, David joined him and together, they finished painting the room in 3 1/3hours. In how many hours will David finish painting the room alone? Answer by fractalier(6550) (Show Source):
You can put this solution on YOUR website! The normal set up is
In our case A = 8, the 1 job is now only 3/4 of a job (since Jon did 1/4 of it already), and the time worked together, t, is 10/3 hours...so we have
We need B. Multiply everything by 8B and get
Now multiply by 3 to clear fractions and get and
B = 10 hours
