document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=156528>Question 156528</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The half-life of strontium-90 is 28 years. How long will it take a 44 mg sample to decay to a mass of 11 mg?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #115326 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=115326\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Half life means you at that time you have 1/2 of what you started with.<BR>\n" );
document.write( "Today you start with 44 mg.<BR>\n" );
document.write( "In 28 years, you will have (1/2)(44)=22 mg left.<BR>\n" );
document.write( "After another 28 years, you will have (1/2)(22)=11 mg left.<BR>\n" );
document.write( "Total time to 11 mg = 56 years. </SPAN>\n" );
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