document.write( "Question 1171305: The population of germs on a toilet seat doubles every 15 mins. How long to the nearest minute, would it take for the population to triple
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Algebra.Com's Answer #796247 by AnlytcPhil(1810)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Instead of doing your problem for you, I'll do a different one that is done\r\n" );
document.write( "exactly the same way, step by step.\r\n" );
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document.write( "I'll do this one:\r\n" );
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\n" ); document.write( "The population of germs on a toilet seat triples every 20 mins. How long to the nearest minute, would it take for the population to quadruple?
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document.write( "\"P=P%5B0%5De%5E%28r%2At%29\"\r\n" );
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document.write( "P0 = original population\r\n" );
document.write( "P = the population after t minutes.\r\n" );
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\n" ); document.write( "The population of germs on a toilet seat triples every 20 mins.
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document.write( "When P=20, P=3∙P0\r\n" );
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document.write( "Substitute in\r\n" );
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document.write( "\"3P%5B0%5D=P%5B0%5De%5E%28r%2A20%29\"\r\n" );
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document.write( "Divide both side by P0\r\n" );
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document.write( "\"3=e%5E%28r%2A20%29\"\r\n" );
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document.write( "Take natural logs of both sides:\r\n" );
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document.write( "\"ln%283%5E%22%22%29=ln%28e%5E%28r%2A20%29%29\"\r\n" );
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document.write( "\"ln%283%5E%22%22%29=r%2A20\"\r\n" );
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document.write( "\"ln%283%29%2F20=r\"\r\n" );
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document.write( "\"1.098612289%2F20=r\"\r\n" );
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document.write( "\"0.0549306144=r\"\r\n" );
document.write( "\r\n" );
document.write( "Substitute in\r\n" );
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document.write( "\"P=P%5B0%5De%5E%280.0549306144%2At%29\"\r\n" );
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document.write( "\"P=P%5B0%5De%5E%280.0549306144%2At%29\"\r\n" );
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\n" ); document.write( "How long to the nearest minute, would it take for the population to quadruple?
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document.write( "Substitute \r\n" );
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document.write( "P=4∙P0\r\n" );
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document.write( "\"4%2AP%5B0%5D=P%5B0%5De%5E%280.0549306144%2At%29\"\r\n" );
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document.write( "Divide both side by P0\r\n" );
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document.write( "\"4=e%5E%280.0549306144%2At%29\"\r\n" );
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document.write( "Take natural logs of both sides:\r\n" );
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document.write( "\"ln%284%29%2F0.0549306144=t\"\r\n" );
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document.write( "\"25.23719016\"\r\n" );
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document.write( "To the nearest minute, every 25 minutes.\r\n" );
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document.write( "Now do yours exactly the same way, step by step.\r\n" );
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document.write( "Edwin
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