document.write( "Question 1195535: Jason forgot that his bicycle was locked up at school, so he ran to the school to get the bicycle, and then rode it back home, his running speed was 9.6kph and his riding speed was 28.8kph, find the distance between his home and school, if the round trip took 20 minutes \n" ); document.write( "

Algebra.Com's Answer #828055 by Alan3354(69443) $\"\"$ $\"About$

You can put this solution on YOUR website!
Jason forgot that his bicycle was locked up at school, so he ran to the school to get the bicycle, and then rode it back home, his running speed was 9.6kph and his riding speed was 28.8kph, find the distance between his home and school, if the round trip took 20 minutes
\n" ); document.write( "--------------------
\n" ); document.write( "The average speed of the round-trip is 2*9.6*28.8/(9.6+28.8) = 19.2*28.8/38.4
\n" ); document.write( "= 14.4 km/hr
\n" ); document.write( "---------
\n" ); document.write( "d = r*t = 14.4*(1/3) = 4.8 km RT
\n" ); document.write( "= 2.4 km each way
\n" ); document.write( "------------------------------
\n" ); document.write( "The formula for average speed of a round-trip, or 2 trips of equal length, is:
\n" ); document.write( " $\"2%2Av%5B1%5D%2Av%5B2%5D%2F%28v%5B1%5D%2Bv%5B2%5D%29\"$
\n" ); document.write( "It's similar to parallel resistance, parallel work, etc., just the factor of 2 is different.
\n" ); document.write( "There are too many formulas for any human to remember them all, but this one is easy. \n" ); document.write( "

\n" );