document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=978183>Question 978183</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The half-life of Radium-226 is 1590 years. If a sample contains 300 mg, how many mg will remain after 4000 years? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #599661 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=599661\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Hi there,<BR>\n" );
document.write( "After 1 half life of 1590 years 150mg of <BR>\n" );
document.write( "original  300 mg will remain radioactive.<BR>\n" );
document.write( "After 2 half lives of a total of 3180 years<BR>\n" );
document.write( "(2 x 1590 yrs) 75 mg of the original 300 mg<BR>\n" );
document.write( "will remain radioactive.<BR>\n" );
document.write( "Now 4000 yrs - 3180 yrs = 820 yrs<BR>\n" );
document.write( "820/1590 = 0.52<BR>\n" );
document.write( "Therefore 0.52 of 75 mg = 38.7 mg<BR>\n" );
document.write( "of the original 300mg will remain radioactive.<BR>\n" );
document.write( "Hope this helps:-) </SPAN>\n" );
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