document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=531116>Question 531116</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If my average mark is 59%, and I get a 90% on my test, what will my new average be? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #350353 by </B><A HREF=/tutors/aboutme.mpl?userid=lmeeks54><B>lmeeks54(111)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=lmeeks54><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=lmeeks54><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=350353\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> From the data given, this question cannot be answered.  That is, when we think about averaging a series of values (e.g., school work/exam scores), and then determining how the average will change with some new potential score, the total number of values being considered in the average calculation is important.<BR>\n" );
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document.write( "Take a couple of simple experiments to test this notion.  Assume there are only two prior grades:<BR>\n" );
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document.write( "57%<BR>\n" );
document.write( "61%<BR>\n" );
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document.write( "The average of these two is 59.0%.  Now add a third score: 90%<BR>\n" );
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document.write( "57%<BR>\n" );
document.write( "61%<BR>\n" );
document.write( "90%<BR>\n" );
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document.write( "The average of these three scores is 69.3%.  That is a jump in class average of >10% for adding that single 90% score.<BR>\n" );
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document.write( "Now consider a 15-week course that meets 3 times per week, and that for each class meeting there is a daily quiz or homework grade.  Then for the 1st 44 weeks, if the average of all grades is 59%, adding one 90% grade will not even change the final average to 60%...<BR>\n" );
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document.write( "Thus, the number of values being considered makes an important difference in the final average.  This could be further complicated by the fact that in many school settings, not all assignments/activities might be weighted equally.  We have no information in this problem statement about weighting the average; however, that is often how grades are calculated.<BR>\n" );
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document.write( "cheers,<BR>\n" );
document.write( "Lee </SPAN>\n" );
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