document.write( "Question 1002742: 6.An anthropologist finds bone that her instruments measure it as 0.177% of the amount of Carbon-14 the bones would have contained when the person was alive. How long ago did the person die?
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document.write( "The half life of carbon 14 is 5,730 years. Round your answer to the nearest thousand.
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Algebra.Com's Answer #619598 by jim_thompson5910(35256)![]() ![]() ![]() You can put this solution on YOUR website! P = orginal amount of carbon 14 t years ago (right when the person died) \n" ); document.write( "A = current amount of carbon 14\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Since \"An anthropologist finds bone that her instruments measure it as 0.177% of the amount of Carbon-14 the bones would have contained when the person was alive\" we know that A = 0.00177P because 0.177% = 0.00177\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The half-life formula in this case is A = P*(1/2)^(t/5730)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "A = P*(1/2)^(t/5730)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "0.00177P = P*(1/2)^(t/5730) Plug in A = 0.00177P\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "0.00177 = (1/2)^(t/5730) Divide both sides by P\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Ln(0.00177) = Ln((1/2)^(t/5730)) Apply natural logs to both sides\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Ln(0.00177) = (t/5730)*Ln(1/2) Use the rule Ln(x^y) = y*Ln(x)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Ln(0.00177)/Ln(1/2) = t/5730 Divide both sides by Ln(1/2)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "5730*Ln(0.00177)/Ln(1/2) = t Multiply both sides by 5730\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "t = 5730*Ln(0.00177)/Ln(1/2) Flip the equation (a = b is the same as b = a)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "t = 52,383.8601165473 Use a calculator\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "t = 52,383.860 Rounding to the nearest thousand (3 decimal places)\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The person died approximately 52,383.860 years ago \n" ); document.write( " |