document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1127611>Question 1127611</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Many physical processes are exponential in nature. A typical way of cleaning a tank of contaminated water is to run in clean water at a constant rate, stir, and let the mixture run out at the same rate. Suppose there are initially 100 pounds of a contaminant in a large tank of water. Assume that the cleaning method described above removes 30% of the remaining contaminant each hour. \r<BR>\n" );
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document.write( "How much contaminant is removed during the first three hours?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #744034 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=744034\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Many physical processes are exponential in nature. A typical way of cleaning a tank of contaminated water is to run in clean water at a constant rate, stir, and let the mixture run out at the same rate. Suppose there are initially 100 pounds of a contaminant in a large tank of water. Assume that the cleaning method described above removes 30% of the remaining contaminant each hour. <BR>\n" );
document.write( "How much contaminant is removed during the first three hours? <BR>\n" );
document.write( "Start:: 100 lbs of contam.<BR>\n" );
document.write( "After one hour:: 0.7*100 = 70 lbs of contam remains<BR>\n" );
document.write( "After 2nd hour:: 0.7*70 = 49 lbs of contam remains<BR>\n" );
document.write( "After 3rd hour:: 0.7*49 = 34.3 lbs of contam remains<BR>\n" );
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document.write( "Answer:: 100 - 0.7^3*100 = 100 - 0.343*100 = 34.3 of contam remains<BR>\n" );
document.write( "Answer:: Amount removed after 3 hrs:: 100 - 34.3 = 65.7 lbs<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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