document.write( "Question 1137736: On a journey of 200 km, a motorist found that if he were to increase his average speed by 2 km/h, the journey would take 15 minutes less. Calculate his average speed \n" ); document.write( "

Algebra.Com's Answer #755607 by josgarithmetic(39617) $\"\"$ $\"About$

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document.write( "              SPEED          TIME               DISTANCE\r\n" );
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document.write( "regular           r                         d\r\n" );
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document.write( "faster            r+2                   d\r\n" );
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document.write( "difference                   \r\n" );
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\r
\n" ); document.write( "\n" ); document.write( " $\"system%28d%2Fr-d%2F%28r%2B2%29=1%2F4%2Cd=200%29\"$
\n" ); document.write( "substitute for d, simplify, and solve for r. \n" ); document.write( "

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