<PRE><B>Question 352577</B>
Each of two brothers can wash a car in 1 hour; however their sister can wash the car in 45 minutes.
If all three work together, how long will it take to wash the car?
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Equation:
rate + rate + rate = together rate
1 + 1 + (1/(3/4)) = 1/x
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2 (4/3) = 1/x
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10/3 = 1/x
x = 3/10 hr
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(3/10)hr = (3/10)60 min = 18 minutes
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They can do it together in 18 minutes.
Cheers,
Stan H.
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