document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1009518>Question 1009518</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Half life/ decay question? Thank you!\r<BR>\n" );
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document.write( "I happen to have 10 pounds of the most radioactive material on Earth buried in my backyard. The half life of the material is 2345 years.\r<BR>\n" );
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document.write( "a.) How long will it take for 5 pounds of the material to decay?<BR>\n" );
document.write( "b.) How long will it take for there to be 2 pounds remaining?<BR>\n" );
document.write( "c.) How much is remaining after 1000 years? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #625063 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39623)</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=625063\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Basic model <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=p%2Ae%5E%28-kt%29 ALIGN=MIDDLE  ALT=\"y=p%2Ae%5E%28-kt%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >'<BR>\n" );
document.write( "y, amount after time t<BR>\n" );
document.write( "p, initial amount for t=0<BR>\n" );
document.write( "k, the decay constant<BR>\n" );
document.write( "t, time passage\r<BR>\n" );
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document.write( "Example for the question mostly uses p=10.<BR>\n" );
document.write( "(a) means, use the half-life;<BR>\n" );
document.write( "(b) means, p=10,y=2, to find t for these.<BR>\n" );
document.write( "(c) means, p=10, t=1000, find y.\r<BR>\n" );
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document.write( "Use algebra and skills with log and exponential functions.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28y%29=ln%28pe%5E%28-kt%29%29 ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28pe%5E%28-kt%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=ln%28y%29=ln%28p%29%2Bln%28e%5E%28-kt%29%29 ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28p%29%2Bln%28e%5E%28-kt%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=ln%28y%29=ln%28p%29-kt%2Aln%28e%29 ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28p%29-kt%2Aln%28e%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28y%29=ln%28p%29-kt%2A1 ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28p%29-kt%2A1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28y%29=ln%28p%29-kt ALIGN=MIDDLE  ALT=\"ln%28y%29=ln%28p%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=kt%2Bln%28y%29=ln%28p%29 ALIGN=MIDDLE  ALT=\"kt%2Bln%28y%29=ln%28p%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=kt=ln%28p%29-ln%28y%29 ALIGN=MIDDLE  ALT=\"kt=ln%28p%29-ln%28y%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight_green%28kt=ln%28p%2Fy%29%29 ALIGN=MIDDLE  ALT=\"highlight_green%28kt=ln%28p%2Fy%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >-----this equation will be used in two ways.\r<BR>\n" );
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document.write( "Maybe you can do the rest of the solution on your own based on this? </SPAN>\n" );
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