document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=282972>Question 282972</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A 6.3 gram sample of an isotope of strotium- 90 was formed in a 1962 explosion of an atomic bomb.  The half- life of strontium- 90 is 28 years.  In what year will only .07 grams remain? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #205461 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><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=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=205461\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .07 = 6.3 (1 / 2)^((x - 1962) / 28)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "log(.07 / 6.3) = ((x - 1962) / 28)[log(1 / 2)]\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "{[log(.07 / 6.3)] / [log(1 / 2)]} * 28 = x - 1962\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "[{[log(.07 / 6.3)] / [log(1 / 2)]} * 28] + 1962 = x </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );