<PRE><B>Question 1051751</B>
A boat can travel 34 mph in still water. If the boat can travel 100 miles with the current in the same time it can travel 80 miles against the current, find the rate of the current r in miles per hour. (Enter an exact number as an integer, fraction, or decimal.) 
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downstream DATA:
dist = 100 miles ; rate = 34+c ; time = 100/(34+c) hrs
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upstream DATA:
dist = 80 miles ; rate = 34-c ; time = 80/(34-c) hrs
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Equation::
100/(34+c) = 80/(34-c)
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3400 - 100c = 2720 + 80c
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680 = 180c
c = 3.78 mph (speed of the current)
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Cheers,
Stan H.
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