document.write( "Question 549986: A truck traveling at an average rate of 45 miles per hour leaves a rest stop. Fifteen minutes later a car traveling at an average rate of 60 miles per hour leaves the same rest stop traveling the same route. How long will it take for the car to catch up with the truck? Thanks!!!! \n" ); document.write( "

Algebra.Com's Answer #358278 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
The truck has a head start of
\n" ); document.write( " $\"+45%2A%281%2F4%29+=+15+\"$ mi
\n" ); document.write( "Start a stopwatch when the car leaves
\n" ); document.write( "Let $\"t\"$ = time on stopwatch when car catches truck
\n" ); document.write( "Let $\"d\"$ = distance car travels until it catches truck
\n" ); document.write( "------------
\n" ); document.write( "Truck's equation:
\n" ); document.write( " $\"+d+-+15+=+45t+\"$
\n" ); document.write( "Car's equation:
\n" ); document.write( " $\"+d+=+60t+\"$
\n" ); document.write( "--------------
\n" ); document.write( "By substitution:
\n" ); document.write( " $\"+60t+-+15+=+45t+\"$
\n" ); document.write( " $\"+15t+=+15+\"$
\n" ); document.write( " $\"+t+=+1+\"$
\n" ); document.write( "It will take the car 1 hour to catch the truck
\n" ); document.write( "--------------
\n" ); document.write( "check:
\n" ); document.write( " $\"+d+-+15+=+45%2A1+\"$
\n" ); document.write( " $\"+d+=+60+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+d+=+60%2A1+\"$
\n" ); document.write( " $\"+d+=+60+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );