SOLUTION: If John can paint a house in 6 hours. Mary can paint one in 4 hours and Sue can paint one in 2 hours, how long would it take them to paint a house if they worked together?
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Question 198387: If John can paint a house in 6 hours. Mary can paint one in 4 hours and Sue can paint one in 2 hours, how long would it take them to paint a house if they worked together? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! If John can paint a house in 6 hours. Mary can paint one in 4 hours
and Sue can paint one in 2 hours, how long would it take them to paint
a house if they worked together?
:
Let t = time required if they all work together
:
Let the completed job = 1
:
Each will paint a fraction of the house. All three fractions add up to 1 + + = 1
Multiply by 12:
12* + 12* + 12* = 12(1)
Cancel out the denominators; results:
2t + 3t + 6t = 12
:
11t = 12
t =
t = 1.09 hrs or 1 hr + .09(60) = 5.45 min
