document.write( "Question 1122555: A man walks from his home to a town 6 km away at a speed of 4 km/h and returns home at a speed of 12 km/h what is man's average speed for the whole journey \n" ); document.write( "

Algebra.Com's Answer #738683 by ikleyn(52799) $\"\"$ $\"About$

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document.write( "Walking at the speed of 4 km/h, the man spends 1.5 hours to cover 6 kilometers.\r\n" );
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document.write( "For the way back, moving at the speed of 12 km/h, he spends 0.5 of an hour.\r\n" );
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document.write( "In all, he spends 1.5 hours + 0.5 of an hour = 2 hours to cover 6 + 6 = 12 kilometers.\r\n" );
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document.write( "It means that his average speed on the way \"to there\" and back is   = 6 kilometers per hour.\r\n" );
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document.write( "    Notice that the average speed in this case  \"6 km/h\" IS NOT the average of the partial speeds  4 km/h  and  12 km/h/\r\n" );
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