document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=212161>Question 212161</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321233832/algebrahomeworkh>Elementary and Intermediate Algebra</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> The decay rate of krypton -85 is 6.3% per year. What is the half-life? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #160247 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=160247\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The decay rate of krypton -85 is 6.3% per year. What is the half-life?<BR>\n" );
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document.write( "A(t) = Ao*(0.937)^t<BR>\n" );
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document.write( "Half-life:<BR>\n" );
document.write( "1/2Ao =Ao*(0.937)^t<BR>\n" );
document.write( "t = ln(1/2)/ln0.937<BR>\n" );
document.write( "t = 10.652 years (half-life)<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "stan H. </SPAN>\n" );
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