document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=852441>Question 852441</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The radioactive substance uranium-240 has a half-life of 14 hours. The amount A(t) of a sample of uranium-240 remaining (in grams) after t hours is given by the following exponential function:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%28t%29=2800%281%2F2%29%5E%28t%2F14%29 ALIGN=MIDDLE  ALT=\"A%28t%29=2800%281%2F2%29%5E%28t%2F14%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "A(t)=2800(1/2)^t/14 (just in case the formula plotting system doesn't work.\r<BR>\n" );
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document.write( "Find the initial amount in the sample and the amount remaining after hours. \r<BR>\n" );
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document.write( " Round your answers to the nearest gram as necessary. \r<BR>\n" );
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document.write( " Initial Amount: \r<BR>\n" );
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document.write( " Amount after 40 hours: </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #513373 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=513373\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Initial amount:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%280%29=2800%2A%281%2F2%29%5E0=2800%2A1=2800 ALIGN=MIDDLE  ALT=\"A%280%29=2800%2A%281%2F2%29%5E0=2800%2A1=2800\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "After 40 hours:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2840%29=2800%2A%281%2F2%29%5E%2840%2F14%29 ALIGN=MIDDLE  ALT=\"A%2840%29=2800%2A%281%2F2%29%5E%2840%2F14%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "My calculator says 0.5^(40/14) is 0.138, and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=A%2840%29=386 ALIGN=MIDDLE  ALT=\"A%2840%29=386\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(I believe it because 40/14 is about 3, and (1/2)^3=1/8=0.125). </SPAN>\n" );
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