Question 280230: boat will go 15 mph in still water,he can go 12 miles down stream in the same time as it takes him to go 9 miles upstream,,then what is the speed of the current
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! boat will go 15 mph in still water,he can go 12 miles down stream in the same time as it takes him to go 9 miles upstream,,then what is the speed of the current
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Downstream DATA:
distance = 12 miles ; rate = 15+c mph ; time = 12/(15+c) hrs
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Upstream DATA:
distance = 9 miles ; rate = 15-c mph ; time = 9/(15-c) hrs
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Equation:
time = time
12/(15+c) = 9/(15-c)
12*15-12c = 9*15+9c
21c = 3*15
current = 2.14 mph
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Cheers,
Stan H.
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