document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=762773>Question 762773</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hand sanitizer kills a certain bacterium 80% of the time on each application.  What is the minimum number of times you must use the hand sanitizer to be 98% certain you have killed that bacterium? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #464307 by </B><A HREF=/tutors/aboutme.mpl?userid=tommyt3rd><B>tommyt3rd(5050)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tommyt3rd><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=tommyt3rd><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=464307\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> We'll write:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P=0.8%5En ALIGN=MIDDLE  ALT=\"P=0.8%5En\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "and 98% implies P=1-0.98 = 0.02\r<BR>\n" );
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document.write( "Solving...\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%28P%29=ln%280.8%5En%29 ALIGN=MIDDLE  ALT=\"ln%28P%29=ln%280.8%5En%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=n=ln%280.02%29%2Fln%280.8%29=17.53 ALIGN=MIDDLE  ALT=\"n=ln%280.02%29%2Fln%280.8%29=17.53\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "so we need to apply 18 times\r<BR>\n" );
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document.write( ":)<BR>\n" );
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