document.write( "Question 1065804: As a rower passes under a bridge, a bottle of whiskey falls into the water.
\n" ); document.write( "Since it's half-full, it floats.
\n" ); document.write( "The rower doesn't hear it, and continues downstream.
\n" ); document.write( "After 20 minutes, he gets thirsty and looks for the bottle.
\n" ); document.write( "Having sobered some, he figures out that it fell into the water.
\n" ); document.write( "He turns around and rows upstream.
\n" ); document.write( "He finds the bottle 1 mile from the bridge.
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\n" ); document.write( "Find the speed of the current. \n" ); document.write( "
Algebra.Com's Answer #681045 by MathTherapy(10552)\"\" \"About 
You can put this solution on YOUR website!

\n" ); document.write( "As a rower passes under a bridge, a bottle of whiskey falls into the water.
\n" ); document.write( "Since it's half-full, it floats.
\n" ); document.write( "The rower doesn't hear it, and continues downstream.
\n" ); document.write( "After 20 minutes, he gets thirsty and looks for the bottle.
\n" ); document.write( "Having sobered some, he figures out that it fell into the water.
\n" ); document.write( "He turns around and rows upstream.
\n" ); document.write( "He finds the bottle 1 mile from the bridge.
\n" ); document.write( "***************
\n" ); document.write( "Find the speed of the current.
\n" ); document.write( "
I found this problem quite interesting, and so decided to solve it.\r
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document.write( "Let speed of boat in still water, and speed of current, be S, and C, respectively
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document.write( "Then average speed going DOWNSTREAM, and UPSTREAM are: S + C, and S – C, respectively
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document.write( "Time bottle (and rower) took to get to MEETUP point = \"matrix%281%2C3%2C+D%2FC%2C+or%2C+1%2FC%29\"
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document.write( "Distance he’d traveled before noticing the missing bottle: \"%2820%2F60%29%28S+%2B+C%29+=+%28S+%2B+C%29%2F3\"
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document.write( "Distance he traveled to get back to bottle: \"%28S+%2B+C%29%2F3+-+1\"
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document.write( "Also, distance he traveled to get back to bottle: 
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document.write( "We then get: \"%28S+%2B+C%29%2F3+-+1++=+%281%2FC+-+1%2F3%29%28S+-+C%29\" 
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document.write( "\"%28S+%2B+C%29%2F3+-+1+=+S%2FC+-+1+-+S%2F3+%2B+C%2F3\"
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document.write( "\"C%28S+%2B+C%29+-+3C+=+3S+-+3C+-+CS+%2B+C%5E2\" -------- Multiplying by LCD, 3C
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document.write( "\"CS+%2B+C%5E2+-+3C+=+3S+-+3C+-+CS+%2B+C%5E2\" 
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document.write( "\"C%5E2+-+C%5E2+%2B+CS+-+3C+-+3S+%2B+3C+%2B+CS+=+0\"
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document.write( "2CS – 3S = 0
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document.write( "S(2C – 3) = S(0)
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document.write( "2C – 3 = 0
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document.write( "2C = 3
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document.write( "C, or speed of current = \"highlight_green%28matrix%281%2C4%2C+3%2F2%2C+or%2C+1.5%2C+mph%29%29\" \n" );
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