document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1113350>Question 1113350</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have worked this problem out several time and keep getting the same answer of  68 mg and 88 minutes. However it keeps saying I am wrong. Here is the problem:\r<BR>\n" );
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document.write( "During surgery, a patient's circulatory system requires at least 50 milligrams of an anesthetic. The amount of anesthetic present t hours after 100 milligrams of anesthetic is administered is given by the following.<BR>\n" );
document.write( "T(t) = 100(0.727)t<BR>\n" );
document.write( "(a) How much, to the nearest milligram, of the anesthetic is present in the patient's circulatory system 20 minutes after the anesthetic is administered?<BR>\n" );
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document.write( "     mg\r<BR>\n" );
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document.write( "(b) How long, to the nearest minute, can the operation last if the patient does not receive additional anesthetic?<BR>\n" );
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document.write( "    min </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #728359 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=728359\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 20 minutes is 1/3 hour.<BR>\n" );
document.write( "t(1/3)=100*(0.727)^(1/3)=100*0.8992=89.92 or 90 minutes<BR>\n" );
document.write( "50=100*0.727^t<BR>\n" );
document.write( "0.5=0.727^t<BR>\n" );
document.write( "ln both sides<BR>\n" );
document.write( "-0.693=t ln (0.727)<BR>\n" );
document.write( "t=-0.6931/-0.3188<BR>\n" );
document.write( "=2.17 hours or 2 hours 10  minutes </SPAN>\n" );
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