document.write( "Question 1065804: As a rower passes under a bridge, a bottle of whiskey falls into the water.
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\n" ); document.write( "Having sobered some, he figures out that it fell into the water.
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Algebra.Com's Answer #680979 by Edwin McCravy(20059)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Suppose the man in the boat in the beginning is traveling south, \r\n" );
document.write( "and when he turns around and comes back he travels north. \r\n" );
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document.write( "What I'm about to tell you to imagine is really weird, but you \r\n" );
document.write( "can imagine it if you try.\r\n" );
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document.write( "Pretend that the river is still and the bank and bridge are\r\n" );
document.write( "moving.  [Yes, I said it was weird!}  The man at first moves \r\n" );
document.write( "south and the bridge moves north.  \r\n" );
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document.write( "Then the bottle stays put and the bridge moves 1 mile north from \r\n" );
document.write( "the bottle for 40 minutes, while the man goes south for 20 minutes\r\n" );
document.write( "and back north to the bottle for another 20 minutes. \r\n" );
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document.write( "[Remember the bottle has not moved at all in the way we are imagining].\r\n" );
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document.write( "So the bridge has moved 1 mile from the bottle in 40 minutes, That's \r\n" );
document.write( "the same as moving 3 miles in 120 minutes or 1.5 miles in 60 minutes \r\n" );
document.write( "or 1.5 miles per hour.\r\n" );
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document.write( "The imagined speed of the bridge is the same as the speed of the\r\n" );
document.write( "current.\r\n" );
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document.write( "Answer 1.5 mph.\r\n" );
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document.write( "Edwin
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