document.write( "Question 474189: At what speed must a biker return from Town B to Town A, a distance of 30 miles, if the trip there took 2 hours and 30 minutes, and he wishes to average 15 miles per hour for the entire trip? \n" ); document.write( "

Algebra.Com's Answer #325210 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi,
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document.write( "Note:  D = r*t  OR r = D/t
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document.write( " r = 30mi/2.5hr = 12mph , the rate to 
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document.write( "  Let x represent rate back...
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document.write( "wishing to average 15mph for the entire trip
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document.write( "    (12mph + x)/2) = 15mph
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document.write( "              x = 18mph \n" );
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