document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=315632>Question 315632</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Students in a biology class just took a final exam.<BR>\n" );
document.write( "A formula for predicting the average exam grade<BR>\n" );
document.write( "on a similar test t months later is<BR>\n" );
document.write( "a) Find the students’ average score when they first<BR>\n" );
document.write( "took the final exam. [12.7]<BR>\n" );
document.write( "b) What would the expected average score be on a<BR>\n" );
document.write( "retest after 4 months? [12.7]<BR>\n" );
document.write( " S(t) = 78 - 15 LOG (t + 1) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #225825 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=225825\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Students in a biology class just took a final exam.<BR>\n" );
document.write( "A formula for predicting the average exam grade<BR>\n" );
document.write( "on a similar test t months later is S(t) = 78 - 15 LOG (t + 1)\r<BR>\n" );
document.write( "\n" );
document.write( "a) Find the students’ average score when they first<BR>\n" );
document.write( "took the final exam.<BR>\n" );
document.write( "--- <BR>\n" );
document.write( "Let t = 0 and solve for S(0)<BR>\n" );
document.write( "S(0) = 78 - 15*log(0+1) = 78-15*log(1)= 78-15*0 = 78<BR>\n" );
document.write( "---------------------------------------------------------<BR>\n" );
document.write( "b) What would the expected average score be on a<BR>\n" );
document.write( "retest after 4 months? <BR>\n" );
document.write( "---<BR>\n" );
document.write( "S(4) = 78-15*log(5) = 78 - 15*0.6990 = 67.52<BR>\n" );
document.write( " <BR>\n" );
document.write( "-----------------------------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "===============<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );