document.write( "Question 78224: Russ and Janet are running in the Apple Hill Fun Run. Russ runs at 7 mph, Janet at 5 mph. If they start at the same time, how long will it be before the are 1/2 mile apart?\r
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Algebra.Com's Answer #56113 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Russ and Janet are running in the Apple Hill Fun Run.\r\n" );
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document.write( "       Want to know what that is?  \r\n" );
document.write( "       It happens every fall in Sacremento CA\r\n" );
document.write( "       http://www.applehillrun.org/race_info.html\r\n" );
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document.write( "Russ runs at 7 mph, Janet at 5 mph. If they start at the\r\n" );
document.write( "same time, how long will it be before the are 1/2 mile apart?\r\n" );
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document.write( "You can do it in your head.  They are separating at the rate \r\n" );
document.write( "of 7-5 or 2 mph.  So in an hour they would be 2 miles apart, \r\n" );
document.write( "so in 15 minutes they will be half a mile apart.  \r\n" );
document.write( "Answer: 15 minutes.\r\n" );
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document.write( "But your teacher probably won't accept that way of doing it. \r\n" );
document.write( "To make your teacher happy, make this DRT chart\r\n" );
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document.write( "         DISTANCE    RATE    TIME\r\n" );
document.write( "Russ                             \r\n" );
document.write( "Janet                           \r\n" );
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document.write( "Let the time it takes them be t.  So fill in\r\n" );
document.write( "t for both their times.\r\n" );
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document.write( "         DISTANCE    RATE    TIME\r\n" );
document.write( "Rus                            t\r\n" );
document.write( "Janet                          t\r\n" );
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document.write( "Now fill in their rates, 7 and 5\r\n" );
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document.write( "         DISTANCE    RATE    TIME\r\n" );
document.write( "Rus                   7        t\r\n" );
document.write( "Janet                 5        t\r\n" );
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document.write( "Now use DISTANCE = RATE × TIME to\r\n" );
document.write( "fill in the distances:\r\n" );
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document.write( "         DISTANCE    RATE    TIME\r\n" );
document.write( "Rus         7t        7        t\r\n" );
document.write( "Janet       5t        5        t\r\n" );
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document.write( "Now we want to find the time when\r\n" );
document.write( "their distances apart are 1/2 mile\r\n" );
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document.write( "Russ' distance MINUS Janet's distance = 1/2 mile\r\n" );
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document.write( "               7t - 5t = 1/2\r\n" );
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document.write( "                    2t = 1/2\r\n" );
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document.write( "Multiply both sides by 2 to clear of fractions:\r\n" );
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document.write( "                    4t = 1\r\n" );
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document.write( "                     t = 1/4 hour\r\n" );
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document.write( "and 1/4 an hour equals 15 minutes.\r\n" );
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document.write( "Edwin

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