document.write( "Question 1153814: \"A truck driver traveled at an average speed of 56 miles per hour on a 200-mile
\n" ); document.write( "trip to pick up a load of freight. On the return trip (with the truck fully
\n" ); document.write( "loaded), the average speed was 37 miles per hour. Find the average speed for the
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\n" ); document.write( "\n" ); document.write( "That is the question, and the answer is 44.6mi/hr.
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Algebra.Com's Answer #776114 by Edwin McCravy(20056) $\"\"$ $\"About$

You can put this solution on YOUR website!
\"A truck driver traveled at an average speed of 56 miles per hour on a 200-mile
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\n" ); document.write( "loaded), the average speed was 37 miles per hour. Find the average speed for the
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document.write( "          Distance|  Rate  |  Time=Distance/Rate\r\n" );
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document.write( "Going    |  200   |   56   |     200/56 hours  \r\n" );
document.write( "Returning|  200   |   37   |     200/37 hours\r\n" );
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document.write( "Total    |  400   |no need | 200/56 + 200/37\r\n" );
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document.write( "Divide every term in the numerator and denominator by 200\r\n" );
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document.write( "Multiply every term in the numerator and denominator by 56∙37 or 2072\r\n" );
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document.write( "[Something interesting that this problem shows is that the average speed is\r\n" );
document.write( "NOT the average of the speeds, even though the truck traveled at each speed\r\n" );
document.write( "for the same distance, 200 miles.  The average of the speeds would be 46.5 mph,\r\n" );
document.write( "which is NOT the right answer!] \r\n" );
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document.write( "Edwin

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