document.write( "Question 502461: Linda drove from Phila. to NYC at the rate of 50 mph. She made the trip from NYC to Phila., along the same route, traveling at 40 mph. Her total driving time was 3.6 hours. Find the distance between Phila. and NYC. \n" ); document.write( "
Algebra.Com's Answer #338885 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Linda drove from Phila. to NYC at the rate of 50 mph.
\n" ); document.write( " She made the trip from NYC to Phila., along the same route, traveling at 40 mph.
\n" ); document.write( " Her total driving time was 3.6 hours.
\n" ); document.write( " Find the distance between Phila. and NYC.
\n" ); document.write( ":
\n" ); document.write( "Let d = dist from Philly to NY
\n" ); document.write( "Write a time equation, time = dist/speed
\n" ); document.write( ":
\n" ); document.write( "To time + return time = 3.6 hrs
\n" ); document.write( "\"d%2F50\" + \"d%2F40\" = 3.6
\n" ); document.write( "multiply by 200 to clear the denominators, results
\n" ); document.write( "4d + 5d = 200(3.6)
\n" ); document.write( "9d = 720
\n" ); document.write( "d = 720/9
\n" ); document.write( "d = 80 mi
\n" ); document.write( ";
\n" ); document.write( ":
\n" ); document.write( "Check this by finding the actual time of each trip
\n" ); document.write( "80/50 = 1.6 hrs
\n" ); document.write( "80/40 = 2.0 hrs
\n" ); document.write( "-----------------
\n" ); document.write( "total: 3.6 hrs \n" ); document.write( "
\n" );