document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1162876>Question 1162876</A>: <I><SPAN STYLE=\"word-break: break-all;\"> After 20 minutes, an initial sample of 192 grams of a radioactive element decays to 6 grams. Determine the half-life of the element. \r<BR>\n" );
document.write( "\n" );
document.write( "this is a grade 11 function, i just want to know how to answer it with the equations and how to solve. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #786779 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=786779\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P=Po(1/2)^t<BR>\n" );
document.write( "P/Po=(1/2)^t<BR>\n" );
document.write( "6/192=(1/32)=(1/2)^t<BR>\n" );
document.write( "log 2 of both sides<BR>\n" );
document.write( "-5=t(-1)<BR>\n" );
document.write( "t=5 half-lives and that was over 20 minutes.  The half-life is 4 minutes<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );