document.write( "Question 1152453: Peggy drives to town at a rate of 40 km/h. How fast must she drive BACK in order to average 80 km/h for the entire trip? \n" ); document.write( "

Algebra.Com's Answer #774475 by ikleyn(52778) $\"\"$ $\"About$

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document.write( "If one-way distance is \"d\" kilometers, then one-way time is  hours.\r\n" );
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document.write( "The two-ways distance (\"to there\" and back) is 2d, and two-ways time is   =  hours.\r\n" );
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document.write( "In other words, at given condition, all the time is spent for one-way distance \"to there\", and there is NO TIME for the way back.\r\n" );
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document.write( "Therefore, the trip under given condition is IMPOSSIBLE.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved, answered and explained. And completed.\r
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