SOLUTION: maria can paint a kitchen in 5 hours and charles can paint the same kitchen in 4 hours. how ing would it take for both working together to paint the kitchen.

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Question 887692: maria can paint a kitchen in 5 hours and charles can paint the same kitchen in 4 hours. how ing would it take for both working together to paint the kitchen.
Answer by Edwin McCravy(20054) About Me  (Show Source):
You can put this solution on YOUR website!
maria can paint a kitchen in 5 hours and charles can paint the same kitchen in 4 hours. how ing would it take for both working together to paint the kitchen. 
Let x be the answer.  Then

%22%22%2B%22%22 %22%22=%22%22 

matrix%281%2C2%2C1%2Ckitchen%29%2Fmatrix%281%2C2%2C5%2Chours%29%22%22%2B%22%22matrix%281%2C2%2C1%2Ckitchen%29%2Fmatrix%281%2C2%2C4%2Chours%29 %22%22=%22%22 matrix%281%2C2%2C1%2Ckitchen%29%2Fmatrix%281%2C2%2Cx%2Chours%29

    

Multiply through by LCD = 20x

    matrix%281%2C7%2C++++4x%2C%22%22%2B%22%22%2C5x%2C%22%22%2C%22%22=%22%22%2C%22%22%2C20%29

    matrix%281%2C5%2C++++9x%2C%22%22%2C%22%22=%22%22%2C%22%22%2C20%29

    matrix%281%2C5%2C++++x%2C%22%22%2C%22%22=%22%22%2C%22%22%2C20%2F9%29

    matrix%281%2C6%2C++++x%2C%22%22%2C%22%22=%22%22%2C%22%22%2C2%262%2F9%2Chours%29

Edwin