document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1171696>Question 1171696</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Paracetamol is a drug used to treat mild to moderate pain and to reduce fever. It has a half-life in the body of 3 hours. Under a Doctor's care, patient N is given a dose of a certain paracetamol. Patient N asks the doctor for another same dose of this paracetamol. The doctor agrees to allow patient N to take dose once there is only 6.25% of the original dose remaining in the body. How long will patient N have to wait, before taking another dose of this paracetamol? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #796610 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52805)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=796610\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "Paracetamol is a drug used to treat mild to moderate pain and to reduce fever. It has a half-life in the body of 3 hours. <BR>\n" );
document.write( "Under a Doctor's care, patient N is given a dose of a certain paracetamol. Patient N asks the doctor for another same dose <BR>\n" );
document.write( "of this paracetamol. The doctor agrees to allow patient N to take dose once there is only 6.25% of the original dose <BR>\n" );
document.write( "remaining in the body. How long will patient N have to wait, before taking another dose of this paracetamol?<BR>\n" );
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document.write( "Notice that  &nbsp;6.25%  &nbsp;is  this ratio &nbsp;&nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=6.25%2F100 ALIGN=MIDDLE  ALT=\"6.25%2F100\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F16 ALIGN=MIDDLE  ALT=\"1%2F16\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2%5E4 ALIGN=MIDDLE  ALT=\"1%2F2%5E4\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "It means that after &nbsp;4 &nbsp;(four) &nbsp;half-life periods the amount of the drug in the body will reach &nbsp;6.25% &nbsp;of the original level.\r<BR>\n" );
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document.write( "So, &nbsp;the &nbsp;<U>ANSWER</U> &nbsp;to the problem's question is  &nbsp;4 &nbsp;times half-life period, &nbsp;or &nbsp;4 x 3 hours = 12 hours.\r<BR>\n" );
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document.write( "You do not need to make long unnecessary calculations to answer the problem's question.\r<BR>\n" );
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