SOLUTION: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?

Algebra ->  Average -> SOLUTION: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?      Log On


   



Question 174500: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
Sally can paint 1/4 of the job per hour
John can paint 1/6 of the job per hour
:
together the can paint (1/4+1/6)of the job per hour
:
LCM is 24
:
6/24+4/24=10/24=5/12( of the job per hour(together))
:
5/12(t)=1(job)
:
cross multiply
:
5t=12
:
highlight%28t=12%2F5=2.4%29hours to complete job together