document.write( "Question 866305: a girl travels 10 km in 50 minutes if she runs for 8 km and walks for 2 km. if she runs for 4 km and walks 6 km, her time is 1 hour 15 minutes. find her running and walking speeds. \n" ); document.write( "
Algebra.Com's Answer #522244 by mananth(16946)\"\" \"About 
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running speed------------x
\n" ); document.write( "walking speed------------y\r
\n" ); document.write( "\n" ); document.write( "t=d/r
\n" ); document.write( "8/x + 2/y = 5/6 ( hours)
\n" ); document.write( "4/x + 6/y = 5/4 (hours)\r
\n" ); document.write( "\n" ); document.write( "let 1/x = a and 1/y =b\r
\n" ); document.write( "\n" ); document.write( "8a+2b=5/6
\n" ); document.write( "4a+6y=5/4\r
\n" ); document.write( "\n" ); document.write( "8 a + 2 b = 5/ 6 .............1
\n" ); document.write( "Total value
\n" ); document.write( "4 a + 6 b = 5/ 4 .............2
\n" ); document.write( "Eliminate y
\n" ); document.write( "multiply (1)by -3
\n" ); document.write( "Multiply (2) by 1
\n" ); document.write( "-24 a -6 b = -5/ 2
\n" ); document.write( "4 a + 6 b = 5/ 4
\n" ); document.write( "Add the two equations
\n" ); document.write( "-20 a = -5/ 4
\n" ); document.write( "/ -20
\n" ); document.write( "a = 1/16
\n" ); document.write( "plug value of a in (1)
\n" ); document.write( "8 a + 2 b = 5/ 6
\n" ); document.write( " 1/ 2 + 2 b = 5/ 6
\n" ); document.write( " 2 b = 5/ 6 -1
\n" ); document.write( " 2 b = 1/ 3
\n" ); document.write( " b = 1/ 6
\n" ); document.write( "a= 1/16 . Therefore x =16 km/h running speed
\n" ); document.write( "b= 1/ 6 Therefore y = 6 km/h walking speed
\n" ); document.write( "m.ananth@hotmail.ca
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