document.write( "Question 930977: Peter cycles to visit his grandmother and then returns home by the same route. He always cycles at 4 km/h when going uphill, 12 km/h when going down hill, and 6 km/h on level ground. If his total cycling time is 2 hours and 20 minutes, what is the total distance he cycles in km? \n" ); document.write( "

Algebra.Com's Answer #565408 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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Peter cycles to visit his grandmother and then returns home by the same route.
\n" ); document.write( " He always cycles at 4 km/h when going uphill, 12 km/h when going down hill, and 6 km/h on level ground.
\n" ); document.write( " If his total cycling time is 2 hours and 20 minutes, what is the total distance he cycles in km?
\n" ); document.write( ":
\n" ); document.write( "let x = the level ground dist
\n" ); document.write( "let y = the hill distance
\n" ); document.write( ":
\n" ); document.write( "Assume grandma is at the top of the hill
\n" ); document.write( "Write a time equation; time = dist/speed
\n" ); document.write( "lev time + uphill time + downhill time + lev time = 2 hr 20 min
\n" ); document.write( " $\"x%2F6\"$ + $\"y%2F4\"$ + $\"y%2F12\"$ + $\"x%2F6\"$ = 2 $\"1%2F3\"$ hrs
\n" ); document.write( "multiply by 12, cancel the denominators
\n" ); document.write( "2x + 3y + y + 2x = 28
\n" ); document.write( "combine like terms
\n" ); document.write( "4x + 4y = 28
\n" ); document.write( "simplify divide by 4
\n" ); document.write( "x + y = 7 km is the one way dist, 14 km is the total distance \n" ); document.write( "

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