document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1024456>Question 1024456</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The value of China's exports of automobiles and parts (in billions of dollars) is approximately f(x)=1.8208e^.3387x, where x = 0 corresponds to 1998.\r<BR>\n" );
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document.write( " In what year did/will the exports reach $5.5 billion?\r<BR>\n" );
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document.write( " Give your answer as the year, with at least one decimal place\r<BR>\n" );
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document.write( "2.  Students in a fifth-grade class were given an exam. During the next 2 years, the same students were retested several times. The average score was given by the model <BR>\n" );
document.write( "f(t)=95&#8722;7log(t+1), 0&#8804;t&#8804;24 where t is the time in months. Round answers to at least 1 decimal point. \r<BR>\n" );
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document.write( " (a) What is the average score on the original exam? <BR>\n" );
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document.write( " (b) What was the average score after 6 months? <BR>\n" );
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document.write( " (c) What was the average score after 18 months? \r<BR>\n" );
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document.write( "  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #692337 by </B><A HREF=/tutors/aboutme.mpl?userid=jorel1380><B>jorel1380(3719)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jorel1380><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=jorel1380><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=692337\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> For the value of exports to reach 5.5 billion, we have:<BR>\n" );
document.write( "5.5=1.8208 e^.3387x <BR>\n" );
document.write( "3.02065=e^.3387x<BR>\n" );
document.write( "ln 3.02065=ln e^.3387x=.3387x<BR>\n" );
document.write( ".3387x=1.1054721272885505026483318585694<BR>\n" );
document.write( "x=3.2638681053692072708837669281647 years after 1998, which equals 2001.2639.\r<BR>\n" );
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document.write( "a)The average score on the original exam was:<BR>\n" );
document.write( "95-7log(t+1)=95-7log(0+1)=95-7log1=95-0=95<BR>\n" );
document.write( "b)After 6 months:<BR>\n" );
document.write( "f(6)=95-7log(6+1)=95-7log7=95-5.92=89.08<BR>\n" );
document.write( "c)After 18 months:<BR>\n" );
document.write( "f(18)=95-7log(18+1)=95-8.95=86.04<BR>\n" );
document.write( "&#9786;&#9786;&#9786;&#9786; </SPAN>\n" );
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