document.write( "Question 485924: Two executives in cities 400 miles apart drive to a business meeting at a location on the line between their cities. They met after 4 hours. Find the speed of each car if one travels 20 miles per hour faster than the other. \n" ); document.write( "

Algebra.Com's Answer #332296 by htmentor(1343) $\"\"$ $\"About$

You can put this solution on YOUR website!
Two executives in cities 400 miles apart drive to a business meeting at a location on the line between their cities. They met after 4 hours. Find the speed of each car if one travels 20 miles per hour faster than the other.
\n" ); document.write( "=============================================================================
\n" ); document.write( "Let d = the distance traveled by the slower car
\n" ); document.write( "Then the distance traveled by the faster car = 400-d
\n" ); document.write( "Let v = the speed of the slower car
\n" ); document.write( "Then v+20 = the speed of the faster car
\n" ); document.write( "Since speed = distance/time, and the time is 4 hrs, we can write the following 2 equations:
\n" ); document.write( "v = d/4 [1]
\n" ); document.write( "v+20 = (400-d)/4 [2]
\n" ); document.write( "Solve for d in [1] and substitute into [2]:
\n" ); document.write( "v+20 = (400-4v)/4
\n" ); document.write( "v+20 = 100-v
\n" ); document.write( "2v = 80
\n" ); document.write( "v = 40 mph
\n" ); document.write( "Therefore, the faster car's speed = 60 mph
\n" ); document.write( " \n" ); document.write( "

\n" );