document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=328263>Question 328263</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need on how to solve this. Please show work. Thanks!\r<BR>\n" );
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document.write( "The Radioactive element americium-241 has a half-life of 432 years. Suppose we start with a 45-g mass of americim-241. How much will be left after 329 years? compute the answer to three significant digits. \r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #235178 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=235178\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Radioactive decay problems are modeled using an exponential function,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%28t%29=N0%2Ae%5E%28kt%29 ALIGN=MIDDLE  ALT=\"N%28t%29=N0%2Ae%5E%28kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where N0 is the initial amount of material, k is a constant for each material. <BR>\n" );
document.write( "Half life means that 1/2 of the initial amount remains. <BR>\n" );
document.write( "We use this to calculate k.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2F2%29N0=N0%2Ae%5E%28k%28432%29%29 ALIGN=MIDDLE  ALT=\"%281%2F2%29N0=N0%2Ae%5E%28k%28432%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=e%5E%28432k%29=%281%2F2%29 ALIGN=MIDDLE  ALT=\"e%5E%28432k%29=%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=432k=ln%281%2F2%29 ALIGN=MIDDLE  ALT=\"432k=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=ln%281%2F2%29%2F432=-1.605x10%5E%28-3%29 ALIGN=MIDDLE  ALT=\"k=ln%281%2F2%29%2F432=-1.605x10%5E%28-3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "So now find N(329).<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=kt=%28329%29%28-1.605x10%5E%28-3%29%29=-0.527883 ALIGN=MIDDLE  ALT=\"kt=%28329%29%28-1.605x10%5E%28-3%29%29=-0.527883\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%28329%29=45%2Ae%5E%28-0.527883%29 ALIGN=MIDDLE  ALT=\"N%28329%29=45%2Ae%5E%28-0.527883%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%28329%29=45%2A%280.58985%29 ALIGN=MIDDLE  ALT=\"N%28329%29=45%2A%280.58985%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=N%28329%29=26.543 ALIGN=MIDDLE  ALT=\"N%28329%29=26.543\"   DISABLED_style= \"max-width:90%; height:auto;\" >grams<BR>\n" );
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