document.write( "Question 1097682: A freight train and a passenger train are in stations 540km apart. The freight train leaves the station at noon travelling at 60km/hr in the direction of the passenger train . One hour later, the passenger train leaves and heads towards the freight train at 90km/h. At what time will the two trains meet.\r
\n" ); document.write( "\n" ); document.write( "I know why one of the equation is 540 = 60x + 90y, but I don't understand why the other equation is x=y+1. Please help me understand. \n" ); document.write( "

Algebra.Com's Answer #712159 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "A freight train and a passenger train are in stations 540km apart. The freight train leaves the station at noon travelling at 60km/hr in the direction of the passenger train . One hour later, the passenger train leaves and heads towards the freight train at 90km/h. At what time will the two trains meet.\r
\n" ); document.write( "\n" ); document.write( "I know why one of the equation is 540 = 60x + 90y, but I don't understand why the other equation is x=y+1. Please help me understand.
\n" ); document.write( "

First of all, it's obvious that you let \"x\" and \"y\" be the times that the freight and passenger trains took, respectively, to get to the catch-up point. 
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document.write( "Now, since the freight train left one hour before the passenger train, and therefore took 1 hour more than the passenger train, to get to the catch-up point,
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document.write( "the TIME equation formed is: Time taken by freight train = Time taken by passenger train, plus 1, OR
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document.write( "                                                       x = y + 1 \n" );
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