document.write( "Question 1095003: A train that is x meters long takes 30 seconds fro the time it first enters a tunnel that is 400 m long, until it is completely through the tunnel. A stationary ceiling light in the tunnel is directly above the train for 10 seconds. Find the value, in meters, of x. \n" ); document.write( "

Algebra.Com's Answer #709590 by ikleyn(52790) $\"\"$ $\"About$

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document.write( "From the condition, the train' speed (rate) is  meters per second.\r\n" );
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document.write( "To go completely through the tunnel, the train must move forward for the length 400+x meters.\r\n" );
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document.write( "It takes exactly 30 seconds, so the distance it moves forward for this time is \r\n" );
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document.write( "Rate*Time =  = 3x.\r\n" );
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document.write( "So, your equation is\r\n" );
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document.write( "400+x = 3x,    (saying that the two distances are the same)\r\n" );
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document.write( "400 = 2x  ====>  x =  = 200 meters.\r\n" );
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document.write( "Answer.  The train is 200 meters long.\r\n" );
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\n" ); document.write( "\n" ); document.write( "There is a bunch of lessons \"on the train\", as a part of Travel and Distance problems.\r
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\n" ); document.write( "\n" ); document.write( "See the lessons\r
\n" ); document.write( "\n" ); document.write( "    - A train passing a telegraph post and passing a bridge \r
\n" ); document.write( "\n" ); document.write( "    - A train passing a platform \r
\n" ); document.write( "\n" ); document.write( "    - A train passing through a tunnel \r
\n" ); document.write( "\n" ); document.write( "    - A light-rail train passing a walking person \r
\n" ); document.write( "\n" ); document.write( "    - A train passing another train \r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook under the section \"Word problems\", the topic \"Travel and Distance problems\".\r
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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I\r
\n" ); document.write( "\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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