document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=132649>Question 132649</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A hot cup of coffee is left outside where it cools exponentially. The temperature, T, of the coffee in degrees Celsius after t minutes is modeled by the function T=66(b)^(x/2)+17. The temperature of the coffee after 9 minutes is 56 degrees Celsius. What is the rate of cooling? <BR>\n" );
document.write( "I think the answer is 3% every two minutes???? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #96943 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=96943\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A hot cup of coffee is left outside where it cools exponentially. The temperature, T, of the coffee in degrees Celsius after t minutes is modeled by the function T=66(b)^(x/2)+17. The temperature of the coffee after 9 minutes is 56 degrees Celsius. What is the rate of cooling? <BR>\n" );
document.write( "I think the answer is 3% every two minutes????<BR>\n" );
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document.write( "T=66(b)^(x/2)+17<BR>\n" );
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document.write( "56 = 66*b^(9/2)+17<BR>\n" );
document.write( "39 = 66*b^(9/2)<BR>\n" );
document.write( "13/22 = b^(9/2)<BR>\n" );
document.write( "Raise both sides to the (2/9) to solve for b:<BR>\n" );
document.write( "b = 0.889666....<BR>\n" );
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document.write( "Formula: <BR>\n" );
document.write( "T(x) = 66*(0.889666)^(x/2) + 17<BR>\n" );
document.write( "T(0) = 66*(1)+17<BR>\n" );
document.write( "T(0) = 83 degrees<BR>\n" );
document.write( "T(9) = 56 degrees<BR>\n" );
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document.write( "Average = (56-83)/9 = -3 degrees per minute<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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