document.write( "Question 1208315: Two trains are approaching each other on parallel tracks. Train A is 1/5 of a mile in length. It travels east at a speed of 40 mph. Train B is 1/8 of a mile in length. It travels west at a speed of 50 mph.\r
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Algebra.Com's Answer #846658 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "Two trains are approaching each other on parallel tracks. Train A is 1/5 of a mile in length.
\n" ); document.write( "It travels east at a speed of 40 mph. Train B is 1/8 of a mile in length. It travels west at a speed of 50 mph.\r
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\n" ); document.write( "\n" ); document.write( "From the moment the trains meet(that is when their noses touch the same plane perpendicular to the tracks),
\n" ); document.write( "how much time elapses until their tails completely pass one another.
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\n" ); document.write( "\n" ); document.write( " For your better understanding, here I will show you \r
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document.write( "The starting moment for our consideration is when the trains noses \r\n" );
document.write( "touch the same plane perpendicular to the tracks.\r\n" );
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document.write( "At this time moment, the ending points of the trains are at the distance\r\n" );
document.write( "equal to the sum of the lengths of trains, i.e.  \r\n" );
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document.write( "     =  =   of a mile.\r\n" );
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document.write( "These two ending points moves/approach toward each other with the speed, \r\n" );
document.write( "which is the sum of the speeds of the trains, i.e. 40 + 50 = 90 miles per hour. \r\n" );
document.write( "It is the relative speed approaching the ending points.\r\n" );
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document.write( "The process will complete when the ending points will meet each other.\r\n" );
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document.write( "The time is  \r\n" );
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document.write( "     =  =  of an hour,\r\n" );
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document.write( "which is 13 seconds.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "It is how physicists think when they solve such problems.\r
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