document.write( "Question 1109022: Margaret drove to a business appointment at 80 mph. Her average speed on the return trip was 70 mph. The return trip took 1/7hr longer because of heavy traffic. How far did she travel to the appointment? \n" ); document.write( "

Algebra.Com's Answer #724053 by greenestamps(13198) $\"\"$ $\"About$

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\n" ); document.write( "The solution by the other tutor is fine. Here is a different possible approach -- based on the idea that for trips of the same distance, the ratio of speeds is the reciprocal of the ratio of times.

\n" ); document.write( "Let x be the time for the trip to the appointment.
\n" ); document.write( "The return trip was at a speed 7/8 of the speed going to the appointment; therefore the amount of time required for the return trip was (8/7)x.
\n" ); document.write( "We know the return trip took 1/7 hour longer than the trip there:
\n" ); document.write( " $\"%288%2F7%29x-x+=+1%2F7\"$
\n" ); document.write( " $\"%281%2F7%29x+=+1%2F7\"$
\n" ); document.write( " $\"x+=+1\"$

\n" ); document.write( "It took her 1 hour to get to the appointment; at 80mph that means the appointment was 80 miles away. \n" ); document.write( "

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