document.write( "Question 1136353: The half-life of Palladium-100 is 4 days. After 20 days a sample of Palladium-100 has been reduced to a mass of 5 mg.
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\n" ); document.write( "What is the mass 4 weeks after the start?
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Algebra.Com's Answer #754112 by josgarithmetic(39618)\"\" \"About 
You can put this solution on YOUR website!
\"y=pe%5E%28-kx%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"1%2F2=1%2Ae%5E%28-k%2A4%29\"\r
\n" ); document.write( "\n" ); document.write( "\"ln%281%2F2%29=ln%28e%5E%28-4k%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"-4k=ln%281%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"k=%281%2F4%29ln%282%29\"\r
\n" ); document.write( "\n" ); document.write( "\"k=%281%2F4%290.69315\"\r
\n" ); document.write( "\n" ); document.write( "\"k=0.17329\"\r
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\n" ); document.write( "\n" ); document.write( "\"highlight_green%28y=pe%5E%28-0.17329x%29%29\"\"model\"\r
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\n" ); document.write( "\n" ); document.write( "5 grams after 20 days:
\n" ); document.write( "\"5=pe%5E%28-0.17329%2A20%29\"\r
\n" ); document.write( "\n" ); document.write( "\"5=p%2Ae%5E%28-3.4658%29\"\r
\n" ); document.write( "\n" ); document.write( "\"5%2F0.01325=p\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28p=160%29\"\"mg\"
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