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 #728358 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=728358\">put this solution on YOUR website!</A><BR><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" );
document.write( " <BR>\n" );
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( "There is a problem with the formula  T(t) = 100(0.727)t  <BR>\n" );
document.write( "… at t=0 it gives you 0 mg, and then goes UP from there<BR>\n" );
document.write( "...<BR>\n" );
document.write( "Please correct and re-post.\r<BR>\n" );
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document.write( "Ok, so its  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+T%28t%29+=+100+%280.727%29%5Et++ ALIGN=MIDDLE  ALT=\"+T%28t%29+=+100+%280.727%29%5Et++\"   DISABLED_style= \"max-width:90%; height:auto;\" >    \r<BR>\n" );
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document.write( "a)   20min must be converted to hours, because the equation wants t in units of hours:<BR>\n" );
document.write( "             20min = 20min*1hr/60min = 1/3 hr\r<BR>\n" );
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document.write( "    T(20min) = T(1/3 hr) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+100%280.727%29%5E%281%2F3%29+=++100%2A0.8992+=+89.92+ ALIGN=MIDDLE  ALT=\"+100%280.727%29%5E%281%2F3%29+=++100%2A0.8992+=+89.92+\"   DISABLED_style= \"max-width:90%; height:auto;\" >,  rounded:   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+highlight%28+90+%29+ ALIGN=MIDDLE  ALT=\"+highlight%28+90+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mg\r<BR>\n" );
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document.write( "b)   50mg is the threshold, so we're looking for t when the  T(t) reaches 50mg:\r<BR>\n" );
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document.write( "    T(t) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+50+=+100+%280.727%29%5Et+ ALIGN=MIDDLE  ALT=\"+50+=+100+%280.727%29%5Et+\"   DISABLED_style= \"max-width:90%; height:auto;\" > <BR>\n" );
document.write( "              <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++1%2F2+=+%280.727%29%5Et+ ALIGN=MIDDLE  ALT=\"++1%2F2+=+%280.727%29%5Et+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "              <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+log%28%281%2F2%29%29+=+t%2Alog%28%280.727%29%29+ ALIGN=MIDDLE  ALT=\"+log%28%281%2F2%29%29+=+t%2Alog%28%280.727%29%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "              <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++t+=+log%28%281%2F2%29%29+%2F+log%28%280.727%29%29+=+%28-0.3010%29+%2F+%28+-0.1385%29+=+2.1733+ ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > hours  =  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+130.398+ ALIGN=MIDDLE  ALT=\"+130.398+\"   DISABLED_style= \"max-width:90%; height:auto;\" > min\r<BR>\n" );
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document.write( "           Rounded to the nearest minute:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+highlight%28+130+%29+ ALIGN=MIDDLE  ALT=\"+highlight%28+130+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > min\r<BR>\n" );
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