document.write( "Question 54013: If Martina leaves home at 9 A.M., bicycling at a rate of
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Algebra.Com's Answer #36271 by AnlytcPhil(1806)\"\" \"About 
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If Martina leaves home at 9 A.M., bicycling at a rate of\r\n" );
document.write( "24 mi/h. About two hours later, John leaves, driving at \r\n" );
document.write( "the rate of 48 mi/h. What will the time be when John \r\n" );
document.write( "catches up with Martina?\r\n" );
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document.write( "Make a DRT-chart:\r\n" );
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document.write( "          Distance    Rate    Time\r\n" );
document.write( "Martina                           \r\n" );
document.write( "John                                 \r\n" );
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document.write( "Fill in their rates (speeds) \r\n" );
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document.write( "          Distance    Rate    Time\r\n" );
document.write( "Martina                24         \r\n" );
document.write( "John                   48         \r\n" );
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document.write( "Let x be the time after 9 o'clock that John catches up\r\n" );
document.write( "with Martina.  So Martina's time is x hours, so fill\r\n" );
document.write( "that in:\r\n" );
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document.write( "          Distance    Rate    Time\r\n" );
document.write( "Martina                24       x\r\n" );
document.write( "John                   48         \r\n" );
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document.write( "Since John started two hours later, his time was 2 hours\r\n" );
document.write( "less than Martina's time.  So his time is x-2 hours. Fill\r\n" );
document.write( "that in \r\n" );
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document.write( "          Distance    Rate    Time\r\n" );
document.write( "Martina                24       x\r\n" );
document.write( "John                   48      x-2\r\n" );
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document.write( "Now use the fact that Distance = Rate × Time to fill in\r\n" );
document.write( "the two distances:\r\n" );
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document.write( "          Distance    Rate    Time\r\n" );
document.write( "Martina      24x       24       x\r\n" );
document.write( "John       48(x-2)     48      x-2\r\n" );
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document.write( "They traveled the same distance, so we can set their\r\n" );
document.write( "distances equal to each other:\r\n" );
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document.write( "  24x = 48(x-2)\r\n" );
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document.write( "Solve that and get x = 4 hours.\r\n" );
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document.write( "Four hours after 9 AM is 1 PM.\r\n" );
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document.write( "Edwin
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