document.write( "Question 1124458: Clara and John are travelling to San Diego from their home. They are going to be driving separate cars as John has to leave 1.2 hours later. Clara drives at an average of 60 miles per hour. John on the other hand drives an average of 70 miles per hour. How long in hours will it take until John catches up with Clara?\r
\n" ); document.write( "\n" ); document.write( "A) 9 hours
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\n" ); document.write( "D) 7.6 hours
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Algebra.Com's Answer #740758 by ikleyn(52786) $\"\"$ $\"About$

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document.write( "Time =  = 7.2 hours = 7 hours and 12 minutes.     // Option E).\r\n" );
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document.write( "At the moment John starts, Clara is 60*1.2 miles ahead.\r\n" );
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document.write( "Their relative speed is  70-60 = 10 miles per hour.\r\n" );
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document.write( "It is the rate of decreasing the distance between them.\r\n" );
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document.write( "Therefore,  the ratio    is the time when John will catch up Clara.\r\n" );
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