document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=857664>Question 857664</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The half-life of a certain substance is 27. How long will it take for a sample of this substances to decay to 88% of it original amount? Use exponential decay model to solve. <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=Aoe%5E%28kt%29 ALIGN=MIDDLE  ALT=\"A=Aoe%5E%28kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #516721 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39617)</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=516721\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Stating the time units for the half-life would be a good thing to do.\r<BR>\n" );
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document.write( "A quantity, I, of the substance drops to I/2 in 27 times units:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2=1%2Ae%5E%28k%2A27%29 ALIGN=MIDDLE  ALT=\"1%2F2=1%2Ae%5E%28k%2A27%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >---simply plugged-in the values about the half life...<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%281%2F2%29=ln%28e%5E%28k%2A27%29%29 ALIGN=MIDDLE  ALT=\"ln%281%2F2%29=ln%28e%5E%28k%2A27%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=27%2Ak%2Aln%28e%29=ln%281%2F2%29 ALIGN=MIDDLE  ALT=\"27%2Ak%2Aln%28e%29=ln%281%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=%281%2F27%29ln%281%2F2%29 ALIGN=MIDDLE  ALT=\"k=%281%2F27%29ln%281%2F2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "The value in decimalized form for k is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28-0.02567%29 ALIGN=MIDDLE  ALT=\"highlight_green%28-0.02567%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "Now your question is, <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=what ALIGN=MIDDLE  ALT=\"t=what\"   DISABLED_style= \"max-width:90%; height:auto;\" > for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A=0.88%2AA%5Bo%5D ALIGN=MIDDLE  ALT=\"A=0.88%2AA%5Bo%5D\"   DISABLED_style= \"max-width:90%; height:auto;\" > ?<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%280.88=1%2Ae%5E%28-0.02567%2At%29%29 ALIGN=MIDDLE  ALT=\"highlight%280.88=1%2Ae%5E%28-0.02567%2At%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "! </SPAN>\n" );
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