document.write( "Question 208157: mike spent 3 hours biking up winding stair mountain, rested for 45 minutes, and biked back 2 hours. how far did he bike if his rate of ascent was 2.5 miles less than his rate of decent? \n" ); document.write( "
Algebra.Com's Answer #157562 by ankor@dixie-net.com(22740)\"\" \"About 
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mike spent 3 hours biking up winding stair mountain, rested for 45 minutes,
\n" ); document.write( " and biked back 2 hours.
\n" ); document.write( " how far did he bike if his rate of ascent was 2.5 miles less than his rate of decent?
\n" ); document.write( ":
\n" ); document.write( "First find the speed:
\n" ); document.write( ":
\n" ); document.write( "Let s = speed descending
\n" ); document.write( "then
\n" ); document.write( "(s-2.5) = speed ascending
\n" ); document.write( ":
\n" ); document.write( "Dist up and back are the same. Write a distance equation: Dist = time * speed
\n" ); document.write( "3(s-2.5) = 2s
\n" ); document.write( "3s - 7.5 = 2s
\n" ); document.write( "3s - 2s = 7.5
\n" ); document.write( "s = 7.5 mph, descending speed
\n" ); document.write( "then
\n" ); document.write( "5 mph, ascending speed
\n" ); document.write( ":
\n" ); document.write( "Find the dist:
\n" ); document.write( "5 * 3 = 15 mi
\n" ); document.write( "and
\n" ); document.write( "2 * 7.5 = 15 mi
\n" ); document.write( ":
\n" ); document.write( "He biked a total of 30 mi up and back \n" ); document.write( "
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