document.write( "Question 1111909: If 35mg of a radioactive element decays to 10mg in only 24 hours, what is its half life? \n" ); document.write( "
Algebra.Com's Answer #726962 by ankor@dixie-net.com(22740)\"\" \"About 
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\n" ); document.write( "If 35 mg of a radioactive element decays to 10mg in only 24 hours,
\n" ); document.write( " what is its half life?
\n" ); document.write( ":
\n" ); document.write( "the radioactive decay formula;
\n" ); document.write( " A = Ao*2^(-t/h)
\n" ); document.write( "where:
\n" ); document.write( "A = amt remain after t time
\n" ); document.write( "Ao = initial amt of the substance
\n" ); document.write( "t = time of decay
\n" ); document.write( "h = half-life of substance
\n" ); document.write( ":
\n" ); document.write( "A = 10
\n" ); document.write( "A = 35
\n" ); document.write( "t = 24 hrs
\n" ); document.write( "find h
\n" ); document.write( "35*2^(-24/h) = 10
\n" ); document.write( "2^(-24/h) = 10/35
\n" ); document.write( "2^(-24/h) = 2/7
\n" ); document.write( "log equiv of exponents
\n" ); document.write( "\"-24%2Fh\"log(2) = \"log%282%2F7%29\"
\n" ); document.write( "\"-24%2Fh\" = \"log%282%2F7%29%2Flog2%29\"
\n" ); document.write( "using the calc
\n" ); document.write( "\"-24%2Fh\" = -1.807355
\n" ); document.write( "h = \"%28-24%29%2F%28-1.807355%29\"
\n" ); document.write( "h = +13.28 hrs is the half life of the substance\r
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