<PRE><B>Question 1045497</B>
Maricris rides her power boat up and down the Agno river. The water in the river flows at 6 miles per hour. Maricris takes 5 hours longer to travel 360 miles against the current than she does to travel 360 miles along with the current. What is the speed of Maricris boat in still water? 
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Upstream DATA:
dist = 360 miles ; time = x+5 hrs ; rate = d/t = 360/(x+5) mph
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Downstream DATA:
dist = 360 miles ; time = x hrs ; rate = 360/x mph
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Equation:
rate - rate = 6 mph
360/x - 360/(x+5) = 6
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360x + 360*5 - 360x = 6x(x+5)
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6x^2 + 30x - 5*360 = 0
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x^2 + 5x - 300 = 0
(x+20)(x-15) = 0 
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Positive solution:
x = 15 hrs
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rate upstream = 360/(x+5) = 360/20 = 18 mph
rate downstream = 360/x = 360/15 = 24 mph
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Equation:
boat speed + current = 24 mph
b + 6 = 24
b = 18 mph (boat speed in calm water)
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Cheers,
Stan H.</PRE>