SOLUTION: Joe can paint their house in 6 days. His father can do the same job in 12 days. How long it take if both working together?

Algebra ->  Rate-of-work-word-problems -> SOLUTION: Joe can paint their house in 6 days. His father can do the same job in 12 days. How long it take if both working together?       Log On


   

Question 333643: Joe can paint their house in 6 days. His father can do the same job in 12 days. How long it take if both working together?


Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Add their rates of working to get the rate that they work together
In words:
(part of the house Joe can paint)/(time it takes to paint it)
plus
(part of the house his Father can paint)/(Father's time to paint it)
equals
(One house painted)/(Their time working together to paint one house)
Given:
Joe's rate of painting:
1%2F6 (the 1 means one house)
Father's rate of painting:
1%2F12
--------------------
1%2F6+%2B+1%2F12+=+1%2Ft
Multiply both sides by 12t
2t+%2B+t+=+12
3t+=+12
t+=+4 days
It takes them 4 days working together