document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=777365>Question 777365</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The radioactive element americium-241 has a half-life of 432 years. Suppose we start with a 20-g mass of americium-241.<BR>\n" );
document.write( "How much will be left after 321 years? Compute the answer to three significant digits. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #474068 by </B><A HREF=/tutors/aboutme.mpl?userid=Cromlix><B>Cromlix(4381)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Cromlix><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=Cromlix><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=474068\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 321/432 * 100 = 74.3%<BR>\n" );
document.write( "74.3% of 20g of americium - 241<BR>\n" );
document.write( "= 14.86g<BR>\n" );
document.write( "20g - 14.86g = 5.14g left active.<BR>\n" );
document.write( "Hope this helps.<BR>\n" );
document.write( ";-) </SPAN>\n" );
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