document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1198346>Question 1198346</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The concentration of a drug in the body fluids is given by C=C0*e^−0.8t, where C0 is the initial dosage and t is the time in hours elapsed after administering the dose.  If 45mg of a drug is given, how much time elapses until 28mg of the drug remains?  Round your answer to two decimal places, if necessary. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #831920 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=831920\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=C=C%5Bo%5De%5E%28-0.8t%29 ALIGN=MIDDLE  ALT=\"C=C%5Bo%5De%5E%28-0.8t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Your question would mean, to solve for t, in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=28=45e%5E%28-0.8t%29 ALIGN=MIDDLE  ALT=\"28=45e%5E%28-0.8t%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, and you could begin by finding logarithms of both sides  (base e). </SPAN>\n" );
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