SOLUTION: Jane and Maria can clean the house in 8 hours if they work together. The time Jane takes in cleaning the house alone is 4 hours more than the time Maria takes in cleaning the same

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Question 889922: Jane and Maria can clean the house in 8 hours if they work together. The time Jane takes in cleaning the house alone is 4 hours more than the time Maria takes in cleaning the same house. How long does it take Jane to clean the house alone?
Answer by lwsshak3(11628) About Me  (Show Source):
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Jane and Maria can clean the house in 8 hours if they work together. The time Jane takes in cleaning the house alone is 4 hours more than the time Maria takes in cleaning the same house. How long does it take Jane to clean the house alone?
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let x=hrs marie takes in cleaning the house alone
1/x=her work rate
x+4=hrs jane takes in cleaning the house alone
1/(x+4)=her work rate
Jane and Maria can clean the house in 8 hours if they work together.
1/8=their work rate
..
sum of indv. work rates=work rate working together
1%2Fx%2B1%2F%28x%2B4%29=1%2F8
lcd:x(x+4)
x+4+x=(x^2+4x)/8
16x+32=x^2+4x
x^2-12x-32=0
solve for x by quadratic formula:
x≈-2.56 (reject)
or
x≈14.25
x+4≈18.25
How long does it take Jane to clean the house alone? 18.25 hrs