document.write( "Question 1179938: Justin can run 10 km in the same amount of time that Leo can run 12 km. If Leo can run 1 kph faster than Justin, how fast can Leo run? \n" ); document.write( "

Algebra.Com's Answer #809498 by ankor@dixie-net.com(22740) $\"\"$ $\"About$

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Let J = Justin's speed in km/hr
\n" ); document.write( "let L = Leo's speed
\n" ); document.write( ":
\n" ); document.write( "Justin can run 10 km in the same amount of time that Leo can run 12 km.
\n" ); document.write( "Write a time equation, time = dist/speed
\n" ); document.write( "j's time = L's time
\n" ); document.write( " $\"10%2Fj\"$ = $\"12%2FL\"$
\n" ); document.write( "cross multiply
\n" ); document.write( "12j = 10L
\n" ); document.write( "simpilfy, divide by 2
\n" ); document.write( "6j = 5L
\n" ); document.write( ":
\n" ); document.write( "If Leo can run 1 kph faster than Justin,
\n" ); document.write( "L = j + 1
\n" ); document.write( "or
\n" ); document.write( "j = L - 1
\n" ); document.write( "how fast can Leo run?
\n" ); document.write( "Replace j with (L-1) in the first equation
\n" ); document.write( "6(L-1) = 5L
\n" ); document.write( "6L - 6 = 5L
\n" ); document.write( "6L - 5L = 6
\n" ); document.write( "L = 6 km/h is Leo's speed
\n" ); document.write( ":
\n" ); document.write( " \n" ); document.write( "

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