document.write( "Question 1186166: Hi
\n" ); document.write( "Henry and Harry drove from a to b 12km away. Henry's average speed was 3km per hour faster than Harry's speed. If Henry reached b 8 minutes faster than Harry, what is Harry's average speed.
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Algebra.Com's Answer #817046 by ikleyn(52797) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "Henry and Harry drove from a to b 12km away. Henry's average speed was 3km per hour faster than Harry's speed.
\n" ); document.write( "If Henry reached b 8 minutes faster than Harry, what is Harry's average speed.
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document.write( "Let x be the slower speed, in km/h.\r\n" );
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document.write( "Then the faster speed is (x+3) km/h.\r\n" );
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document.write( "Now you write the \"time\" equation\r\n" );
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document.write( "     -  =   of an hour.    (1)\r\n" );
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document.write( "Simplify it\r\n" );
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document.write( "     -  = \r\n" );
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document.write( "     = \r\n" );
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document.write( "     = \r\n" );
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document.write( "    x*(x+3) = 15*18.\r\n" );
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document.write( "From this point, you  GUESS  the  ANSWER  MENTALLY  and momentarily:  x = 15 km/h.\r\n" );
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document.write( "ANSWER.  Harry's average speed is 15 km/h.\r\n" );
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document.write( "CHECK.   -  =  =  = ,   exactly as in equation (1).  ! Correct !\r\n" );
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