document.write( "Question 839516: you travel 350 miles in the same amount of time it takes a friend to travel 400 miles. your friends average speed is 4 miles per hour greater than your average speed. find your friends average speed \n" ); document.write( "

Algebra.Com's Answer #505734 by mananth(16946) $\"\"$ $\"About$

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My speed x mph
\n" ); document.write( "Friend's speed 4 faster x + 4 mph
\n" ); document.write( "
\n" ); document.write( "My speed 350 miles
\n" ); document.write( "Friend's speed 400 miles
\n" ); document.write( "My time = Friend's time
\n" ); document.write( "t=d/r
\n" ); document.write( "350 / x = 400 /( x + 4 )
\n" ); document.write( "cross multiply
\n" ); document.write( "350 ( x + 4 ) = 400 x
\n" ); document.write( "350 x + 1400 = 400 x
\n" ); document.write( "350 x - 400 x = -1400
\n" ); document.write( "-50 x = -1400
\n" ); document.write( "/ -50
\n" ); document.write( "x = 28 mph
\n" ); document.write( "
\n" ); document.write( "150 mph My speed
\n" ); document.write( "154 mph Friend's speed
\n" ); document.write( " \n" ); document.write( "

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