document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=511780>Question 511780</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The average grade of two classes is 88. One class has 30 students with an average grade of 84. If the average of the second class is 96, how many students does the second class have? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #342396 by </B><A HREF=/tutors/aboutme.mpl?userid=oberobic><B>oberobic(2304)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oberobic><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=342396\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The arithmetic average = total of all students' scores / number of students.<BR>\n" );
document.write( "avg = total/count<BR>\n" );
document.write( "so<BR>\n" );
document.write( "count*avg = total<BR>\n" );
document.write( ".<BR>\n" );
document.write( "We do not know the count in the second class, but we know the average, so we can use the average.<BR>\n" );
document.write( "The count in the second class = x.<BR>\n" );
document.write( "So the combined count in the two classes = 30+x.<BR>\n" );
document.write( ".<BR>\n" );
document.write( "30*84 + x*96 = (30+x)*88<BR>\n" );
document.write( ".<BR>\n" );
document.write( "2520 + 96x = 2640 +88x<BR>\n" );
document.write( "8x = 120<BR>\n" );
document.write( "x = 15<BR>\n" );
document.write( "There are 15 students in the second class.<BR>\n" );
document.write( ".<BR>\n" );
document.write( "Done. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );