document.write( "Question 1195759: The radioactive element​ carbon-14 has a​ half-life of 5750 years. A scientist determined that the bones from a mastodon had lost 60.4​% of their​ carbon-14. How old were the bones at the time they were​ discovered?
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Algebra.Com's Answer #828281 by josgarithmetic(39627)\"\" \"About 
You can put this solution on YOUR website!
Often chosen equation model, \"y=pe%5E%28-kx%29\"
\n" ); document.write( "y, amount present after x time passed
\n" ); document.write( "p, amount initial
\n" ); document.write( "k, decay constant\r
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\n" ); document.write( "\n" ); document.write( "HALF-LIFE, C-14
\n" ); document.write( "\"1%2F2=1%2Ae%5E%28-k%2A5750%29\"\r
\n" ); document.write( "\n" ); document.write( "\"e%5E%28-k%2A5750%29=1%2F2\"\r
\n" ); document.write( "\n" ); document.write( "\"ln%28e%5E%28-5750k%29%29=ln%281%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"-5750k=ln%281%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"k=%28-1%2F5750%29ln%281%2F2%29\"\r
\n" ); document.write( "\n" ); document.write( "\"k=%281%2F5750%29ln%282%29\"\r
\n" ); document.write( "\n" ); document.write( "\"k=0.000120547\"\r
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\n" ); document.write( "\n" ); document.write( "Example indicates p=100, y=100-60.4=39.6.\r
\n" ); document.write( "\n" ); document.write( "\"y=pe%5E%28-kx%29\"\r
\n" ); document.write( "\n" ); document.write( "\"ln%28y%29=ln%28p%29%2Bln%28e%5E%28-kx%29%29\"\r
\n" ); document.write( "\n" ); document.write( "\"ln%28y%29-ln%28p%29=-kx\"\r
\n" ); document.write( "\n" ); document.write( "\"ln%28y%2Fp%29=-kx\"\r
\n" ); document.write( "\n" ); document.write( "\"x=-%281%2Fk%29ln%28y%2Fp%29\"\r
\n" ); document.write( "\n" ); document.write( "\"x=-%281%2F0.000120547%29ln%280.396%29\"\r
\n" ); document.write( "\n" ); document.write( "\"highlight_green%28x=7680%29\"
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