SOLUTION: A man can paint a room in 8 hours. It takes his son 12 hours to do the same job. After working by himself for 2 hours, his son joined him and together they finished the job. How lo

Question 1088529: A man can paint a room in 8 hours. It takes his son 12 hours to do the same job. After working by himself for 2 hours, his son joined him and together they finished the job. How long did the son work?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
The man's rate of working is
[ 1 room painted ] / [ 8 hrs ] =
-------------------------------------
[ rate ] x [ time in hrs ] = [ fraction of the job completed ]

That means there is of the job left to do
----------------------------------------------------
Add their rates of working to get the rate at which
they will finish 3/4 of the job in hrs

Multiply both sides by

The son worked for 3 hrs and 36 min
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Get a 2nd opinion if needed

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