document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=928743>Question 928743</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If 18g of a radioactive substance are present initially and 5 yr later only 9 g remain, how much of the substance will be present after 11yr ?<BR>\n" );
document.write( "after 11yr there will be ___g of a radioactive substance.<BR>\n" );
document.write( "round the final answer to the nearest thousandth as needed. round all intermediate values to the nearest thousandth as needed. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #563831 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39627)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=563831\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Decay equation <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=p=18%2Ae%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"p=18%2Ae%5E%28-kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > and you first want to take the given data and use to find k.  t is time in years, p is quantity remaining after time t.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28p%29=ln%2818%29-kt ALIGN=MIDDLE  ALT=\"ln%28p%29=ln%2818%29-kt\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28p%29-ln%2818%29=-kt ALIGN=MIDDLE  ALT=\"ln%28p%29-ln%2818%29=-kt\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-k=%28ln%28p%29-ln%2818%29%29%2Ft ALIGN=MIDDLE  ALT=\"-k=%28ln%28p%29-ln%2818%29%29%2Ft\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=%28ln%2818%29-ln%28p%29%29%2Ft ALIGN=MIDDLE  ALT=\"k=%28ln%2818%29-ln%28p%29%29%2Ft\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Substitute the given data point:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28k=%281%2F5%29ln%282%29%29 ALIGN=MIDDLE  ALT=\"highlight_green%28k=%281%2F5%29ln%282%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and you can compute this value yourself of k.\r<BR>\n" );
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document.write( "How much is p at t=11?<BR>\n" );
document.write( "You know k now, and given t.<BR>\n" );
document.write( "Evaluate p. </SPAN>\n" );
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