SOLUTION: A boat takes 8 hours to go 6 miles upstream and come back to the starting point. If the speed of the boat is 4 miles per hour in still water, what is the rate of the current?

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Question 750544: A boat takes 8 hours to go 6 miles upstream and come back to the starting point. If the speed of the boat is 4 miles per hour in still water, what is the rate of the current?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A boat takes 8 hours to go 6 miles upstream and come back to the starting point. If the speed of the boat is 4 miles per hour in still water, what is the rate of the current?
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Upstream DATA:
time = x hrs ; distance = 6 miles ; rate = d/t = 6/x hrs
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Downstream DATA:
time = 8-x hrs ; distance = 6 miles ; rate = d/t = 6/(8-x)
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Equation:
Upstream Rate Eq::: 4-c = 6/x
Downstream Rt Eq::: 4+c = 6/(8-x)
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Add to solve for "x":
8 = (6/x)+(6/(8-x))
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8x(8-x) = 6(8-x) + 6x
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64x - 8x^2 = 48
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x^2 - 8x + 48 = 0
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No Real Number solution.
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Cheers,
Stan H.
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