document.write( "Question 542971: My teacher went over these problems in class today. I know that I would set up a chart to help me solve the problem, but I get stuck on how to determine the t in D=rt. Please help me!!! Thanks!!!\r
\n" ); document.write( "\n" ); document.write( "Two trains leave a station at the same time, heading in opposite directions. One train is traveling at 80 km/h, the other at 90 km/h. How long will it take for the trains to be 425 km apart? \n" ); document.write( "
Algebra.Com's Answer #354715 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
Two trains leave a station at the same time, heading in opposite directions. One train is traveling at 80 km/h, the other at 90 km/h. How long will it take for the trains to be 425 km apart?
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\n" ); document.write( "1st train DATA:
\n" ); document.write( "rate = 80 km/hr ; time = t hrs ; distance = 80t km
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\n" ); document.write( "2nd train DATA:
\n" ); document.write( "rate = 90 km/hr ; time = t hrs ; distance = 90t km
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\n" ); document.write( "Equation:
\n" ); document.write( "distance + distance = 425 km
\n" ); document.write( "80t + 90t = 425
\n" ); document.write( "170t = 425
\n" ); document.write( "t = 2.5 hours
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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