document.write( "Question 122400: A passenger train leaves New York City traveling west at 130 km/hr. Three hours later, a freight train leaves the same station, traveling west at 160 km/hr. How many hours will each train travel before the second train catches up with the first? \n" ); document.write( "
Algebra.Com's Answer #89867 by ankor@dixie-net.com(22740)\"\" \"About 
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A passenger train leaves New York City traveling west at 130 km/hr. Three hours later, a freight train leaves the same station, traveling west at 160 km/hr. How many hours will each train travel before the second train catches up with the first?
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\n" ); document.write( "One important fact to remember in these kind of \"catch-up\" problems is:
\n" ); document.write( "When they catch up they will have traveled the same distance.
\n" ); document.write( "We can make a simple equation from this fact:
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\n" ); document.write( "Let t = time required for the 2nd train to catch up
\n" ); document.write( "then
\n" ); document.write( "(t+3) = travel time of the 1st train when it is caught
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\n" ); document.write( "Dist = speed * time
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\n" ); document.write( "2nd train dist = 1st train dist
\n" ); document.write( "160t = 130(t+3)
\n" ); document.write( "160t = 130t + 390
\n" ); document.write( "160t - 130t = 390
\n" ); document.write( "30t = 390
\n" ); document.write( "t = \"390%2F30\"
\n" ); document.write( "t = 13 hrs for the 2nd train to catch up
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\n" ); document.write( "Check solution by finding the distance, they should be equal
\n" ); document.write( "1st train time 13 + 3 = 16 hr
\n" ); document.write( "160 * 13 = 2080 km
\n" ); document.write( "130 * 16 = 2080 km; confirms our solution
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\n" ); document.write( "This wasn't that hard, was it?\r
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