SOLUTION: sally can paint the house in 4 hours and john can paint it in 6 hours. how long will it take the two of them to paint the house together?

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Question 3221: sally can paint the house in 4 hours and john can paint it in 6 hours. how long will it take the two of them to paint the house together?
Found 2 solutions by mixerimaythyme, 303795:
Answer by mixerimaythyme(7) About Me  (Show Source):
You can put this solution on YOUR website!
simpliy, you are finding the average of the two when they both paint a house...
in order to find the average, you add 4 hrs with 6 hrs (which gives you 10 hrs),
then divide by how many numbers you added, (which in this case is 2)...
10/2=5
Both of them painting a house together only takes about 5 hours according to the problem you had given me...

Answer by 303795(602) About Me  (Show Source):
You can put this solution on YOUR website!
Sally takes 4 hours to paint the house so she paints 1/4 of the house per hour.
John takes 6 hours so he paints 1/6 of the house per hour.
In one hour they paint 1/4 + 1/6 of the house.
1%2F4+%2B+1%2F6+=+3%2F12+%2B+2%2F12+=+%285%2F12%29+of+the+house To paint the whole house will take 12/5 of an hour
ie 2 hours and 24 minutes.