document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1171697>Question 1171697</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A certain pain reliever has a half-life of 16 hours. If the initial plasma level of this pain reliever, given as a single dose, is 512mg/L, how long will it take for the plasma level to fall to 16mg/L? </SPAN>\n" );
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document.write( "A certain pain reliever has a half-life of 16 hours. If the initial plasma level of this pain reliever, <BR>\n" );
document.write( "given as a single dose, is 512mg/L, how long will it take for the plasma level to fall to 16mg/L?<BR>\n" );
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document.write( "Notice that the ratio of  &nbsp;16 mg/L  to &nbsp;512 mg/L  is  &nbsp;&nbsp;<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16%2F512 ALIGN=MIDDLE  ALT=\"16%2F512\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F32 ALIGN=MIDDLE  ALT=\"1%2F32\"   DISABLED_style= \"max-width:90%; height:auto;\" > = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F2%5E5 ALIGN=MIDDLE  ALT=\"1%2F2%5E5\"   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
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document.write( "It means that after &nbsp;5 &nbsp;(five) &nbsp;half-life periods the original concentration \r<BR>\n" );
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document.write( "of the drug in the plasma will decrease from the original  &nbsp;512 mg/L to &nbsp;16 mg/L.\r<BR>\n" );
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document.write( "So, &nbsp;the &nbsp;<U>ANSWER</U> &nbsp;to the problem's question is  &nbsp;5 &nbsp;times half-life periods, &nbsp;or &nbsp;5 x 16 hours = 80 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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