SOLUTION: If Sally can paint a house in 4 hours and John can paint the same house in 6 hours. How long will it take them to paint the house together? Can someone please tell me how to solve

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Question 305903: If Sally can paint a house in 4 hours and John can paint the same house in 6 hours. How long will it take them to paint the house together? Can someone please tell me how to solve this?
Found 2 solutions by richwmiller, Earlsdon:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
This same problem has appeared daily for a week now.

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
1) Find the hourly rate of each painter.
If Sally can paint the house in 4 hours, then she can paint 1%2F4 of the house in 1 hour.
If John can paint the house in 6 hours, then he can paint 1%2F6 of the house in 1 hour.
2) Find the hourly rate when working together.
Together, they can paint 1%2F4%2B1%2F6+=+10%2F24 of the house in 1 hour.
3) Find the time to paint the entire house together.
They can paint the whole house in 24%2F10+=+2.4hours or 2 hours and 24 minutes.