document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=824799>Question 824799</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Solve the problem.\r<BR>\n" );
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document.write( "A thermometer reading 9°C is brought into a room with a constant temperature of 30°C. If the thermometer reads 15°C after 3 minutes, what will it read after being in the room for 6 minutes? Assume the cooling follows Newton's Law of Cooling: U = T + (Uo - T)e^kt. (Round your answer to two decimal places.)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #496791 by </B><A HREF=/tutors/aboutme.mpl?userid=KMST><B>KMST(5328)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=KMST><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=KMST><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=496791\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U+=+T+%2B+%28U%5B0%5D+-+T%29e%5Ekt ALIGN=MIDDLE  ALT=\"U+=+T+%2B+%28U%5B0%5D+-+T%29e%5Ekt\"   DISABLED_style= \"max-width:90%; height:auto;\" > where<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U ALIGN=MIDDLE  ALT=\"U\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the reading at time <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t ALIGN=MIDDLE  ALT=\"t\"   DISABLED_style= \"max-width:90%; height:auto;\" > minutes since the thermometer enters a new temperature zone,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U%5B0%5D%7D%7D+is+the+reading+at+%7B%7B%7Bt=0 ALIGN=MIDDLE  ALT=\"U%5B0%5D%7D%7D+is+the+reading+at+%7B%7B%7Bt=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > in degrees Celsius, and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T ALIGN=MIDDLE  ALT=\"T\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the true temperature.<BR>\n" );
document.write( " <BR>\n" );
document.write( "After 3 minutes<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=3 ALIGN=MIDDLE  ALT=\"t=3\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the time the thermometer has been in the room, in minutes,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U%5B0%5D=9 ALIGN=MIDDLE  ALT=\"U%5B0%5D=9\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the reading at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=0 ALIGN=MIDDLE  ALT=\"t=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > in degrees Celsius, and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T=30 ALIGN=MIDDLE  ALT=\"T=30\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the true temperature of the room.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U=15 ALIGN=MIDDLE  ALT=\"U=15\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15=30%2B%289-30%29e%5E%283k%29 ALIGN=MIDDLE  ALT=\"15=30%2B%289-30%29e%5E%283k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=15-30=%289-30%29e%5E%283k%29 ALIGN=MIDDLE  ALT=\"15-30=%289-30%29e%5E%283k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-15=-21e%5E%283k%29 ALIGN=MIDDLE  ALT=\"-15=-21e%5E%283k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-15%29%2F%28-21%29=e%5E%283k%29 ALIGN=MIDDLE  ALT=\"%28-15%29%2F%28-21%29=e%5E%283k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2F7=e%5E%283k%29 ALIGN=MIDDLE  ALT=\"5%2F7=e%5E%283k%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=ln%285%2F7%29=3k ALIGN=MIDDLE  ALT=\"ln%285%2F7%29=3k\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k=ln%28%225%2F7%22%29%2F3 ALIGN=MIDDLE  ALT=\"k=ln%28%225%2F7%22%29%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(You can calculate this <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k ALIGN=MIDDLE  ALT=\"k\"   DISABLED_style= \"max-width:90%; height:auto;\" > number to use later, if you like.<BR>\n" );
document.write( "Your calculator will hold enough digits in its memory to make your rounded final answer accurate.<BR>\n" );
document.write( "If you write the <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k ALIGN=MIDDLE  ALT=\"k\"   DISABLED_style= \"max-width:90%; height:auto;\" > value down, to re-enter it into the calculator later, make sure to write down enough digits.<BR>\n" );
document.write( "I trust my calculator and my ability to use it, but prefer not to calculate <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=k ALIGN=MIDDLE  ALT=\"k\"   DISABLED_style= \"max-width:90%; height:auto;\" > at this point).<BR>\n" );
document.write( " <BR>\n" );
document.write( "For what we want to calculate<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=6 ALIGN=MIDDLE  ALT=\"t=6\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the time the thermometer has been in the room, in minutes,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U%5B0%5D=9 ALIGN=MIDDLE  ALT=\"U%5B0%5D=9\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the reading at <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=t=0 ALIGN=MIDDLE  ALT=\"t=0\"   DISABLED_style= \"max-width:90%; height:auto;\" > in degrees Celsius, and<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=T=30 ALIGN=MIDDLE  ALT=\"T=30\"   DISABLED_style= \"max-width:90%; height:auto;\" > is the true temperature of the room.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=U=30%2B%289-30%29e%5E%286%2A%22ln%285%2F7%29%22%2F3%29=30-21e%5E%282%2Aln%285%2F7%29%29=30-21%28e%5Eln%285%2F7%29%29%5E2=30-21%285%2F7%29%5E2=30-3%2Across%287%29%2A%2825%2F%287%2Across%287%29%29%29=30-75%2F7=highlight%2819.29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > (rounded to 2 decimal places) </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );