document.write( "Question 903876: Find the associated exponential decay or growth model.
\n" ); document.write( "Q = 2,500 when t = 0; half-life = 5
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Algebra.Com's Answer #548377 by josgarithmetic(39617) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"Q=q%2Ae%5E%28kt%29\"$ using q=2500, and I am using two variables differently than are you.\r
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\n" ); document.write( "\n" ); document.write( "Your half-life information goes this way:
\n" ); document.write( "t for half life is t=5.
\n" ); document.write( "Q=(1/2)q, so form a more specific equation as:
\n" ); document.write( " $\"1%2F2=1%2Ae%5E%28k%2A5%29\"$
\n" ); document.write( " $\"ln%281%2F2%29=ln%28e%5E%285k%29%29\"$
\n" ); document.write( " $\"5k%2A1=ln%281%2F2%29\"$
\n" ); document.write( " $\"k=%281%2F5%29ln%281%2F2%29\"$
\n" ); document.write( " $\"highlight%28k=-%281%2F5%29ln%282%29%29\"$ , for a decimal value of approximately $\"-0.139\"$ .\r
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\n" ); document.write( "\n" ); document.write( "Model to use, $\"highlight%28Q=2500%2Ae%5E%28-0.139%2At%29%29\"$ . \n" ); document.write( "

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