document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=131727>Question 131727</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am doing a unit on geometric/arithmetic series and sequences.<BR>\n" );
document.write( "Here is the problem:\r<BR>\n" );
document.write( "\n" );
document.write( "Determine S25 for 3 + 3x2 + 3x4 + 3x6 + . . . <BR>\n" );
document.write( "I know that this is a geometric series and a=3.<BR>\n" );
document.write( "I know I will use the formula:  S25 =(1-rn)/1-r,\r<BR>\n" );
document.write( "\n" );
document.write( "but I cannot figure out what the r is? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #102714 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=102714\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (3x^2)/3 = x^2<BR>\n" );
document.write( "so r = x^2<BR>\n" );
document.write( "===============<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );