document.write( "Question 1109003: It took Eric 11 hours to drive to a family reunion. On the way home, he was able to increase his average speed by 18mph and make the return drive in only 8 hpurs. Find his average speed on the return drive. \n" ); document.write( "

Algebra.Com's Answer #724019 by ikleyn(52810) $\"\"$ $\"About$

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document.write( "The \"distance\" equation\r\n" );
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document.write( "    11*(r-18) = 8*r,      (saying that the distance in both ways is the same)\r\n" );
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document.write( "where \"r\" is the average speed on the return drive (which is under the question).\r\n" );
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document.write( "11r - 11*18 = 8r  ====>  11r - 8r = 11*18  ====>  3r = 11*18  ====>  r =  = 66.\r\n" );
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document.write( "Answer.  The average speed on the return trip was 66 miles per hour.\r\n" );
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\n" ); document.write( "To see other similar introductory Travel and Distance problems, see the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Travel and Distance problems \r
\n" ); document.write( "\n" ); document.write( "    - Travel and Distance problems for two bodies moving in opposite directions \r
\n" ); document.write( "\n" ); document.write( "    - Travel and Distance problems for two bodies moving in the same direction (catching up)\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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