document.write( "Question 998808: Joy is riding her bicycle up a hill. After travelling 3km, Joy passes Greg who is walking down the hill at a rate of 1m/s. Joy continues up the hill for another 7km before riding down the hill double the average speed she went up. Joy ang Greg meet at Joy's starting point at the same moment. In meters per second, what was Joy's average speed going down the hill? \n" ); document.write( "
Algebra.Com's Answer #616559 by mananth(16946)\"\" \"About 
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\n" ); document.write( "\n" ); document.write( "Joy rides7 km = 7000 m at x m/s\r
\n" ); document.write( "\n" ); document.write( "time up = 7000/x\r
\n" ); document.write( "\n" ); document.write( "time down = 10000/2x\r
\n" ); document.write( "\n" ); document.write( "Time up + time down for joy = time by greg to reach the starting\r
\n" ); document.write( "\n" ); document.write( "7000/x + 10000/2x = 3000\r
\n" ); document.write( "\n" ); document.write( "multiply by 2x\r
\n" ); document.write( "\n" ); document.write( "14000 +10000 = 2x*3000\r
\n" ); document.write( "\n" ); document.write( "24000 = 6000x\r
\n" ); document.write( "\n" ); document.write( "x = 4 m/s up the hill\r
\n" ); document.write( "\n" ); document.write( "downhill 4*2 = 8 m/s
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