document.write( "Question 1204384: A train travels to Chicago, empty, at 70 mph. It returns loaded at 60 mph. If total travel time is 6 hours and 30 minutes, how far from Chicago is the starting point? \n" ); document.write( "

Algebra.Com's Answer #840589 by ikleyn(52776) $\"\"$ $\"About$

You can put this solution on YOUR website!
.
\n" ); document.write( "

\r\n" );
document.write( "\r\n" );
document.write( "Let \"d\" be the distance from Chicago.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "Moving with the speed 70 mph, the train spends    hours one way.\r\n" );
document.write( "\r\n" );
document.write( "Moving with the speed 60 mph, the train spends    hours another way (but the same distance).\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "So, we write this  total time two-ways travel equation \r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "     +  = 6.5  hours.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "To solve, multiply both sides by 420.  You will get\r\n" );
document.write( "\r\n" );
document.write( "    6d + 7d = 6.5*420,\r\n" );
document.write( "\r\n" );
document.write( "or\r\n" );
document.write( "\r\n" );
document.write( "      13d   = 2730,\r\n" );
document.write( "\r\n" );
document.write( "        d   = 2730/13 = 210.\r\n" );
document.write( "\r\n" );
document.write( "\r\n" );
document.write( "ANSWER.  One-way distance from Chicago is 210 miles.\r\n" );
document.write( "

\r
\n" ); document.write( "\n" ); document.write( "Solved.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "-------------------\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Looks as a miracle ?\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "- - - It is REALLY a miracle. It is how the \" time equation \" works.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "

\n" );