document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=36866>Question 36866</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0030522234/algebrahomeworkh>Algebra 2</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> I have tried to do the problem <BR>\n" );
document.write( "\"For each arithmetic series, find S of 25\"<BR>\n" );
document.write( "  3+7+11+15<BR>\n" );
document.write( "This is the equation i came up with<BR>\n" );
document.write( "25[2(3)+(25-1)d/2]<BR>\n" );
document.write( "I just cant find the d and when i try my answer comes out incorrect..<BR>\n" );
document.write( "thanks.. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #22649 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=22649\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> For each arithmetic series, find S of 25\"<BR>\n" );
document.write( "3+7+11+15\r<BR>\n" );
document.write( "\n" );
document.write( "S(25) means to find the sum of the 1st 25 terms.<BR>\n" );
document.write( "d is the difference between any term and the previous term:<BR>\n" );
document.write( "For your problem d=11-7=4<BR>\n" );
document.write( "The Sum formula is S(n)=(n/2)(a(1)+a(n))<BR>\n" );
document.write( "and a(n)=a(1)+(n-1)d<BR>\n" );
document.write( "Since a(1)=3, a(25)=3+(24)(4)=99<BR>\n" );
document.write( "Therefore S(25)=(25/2)(3+99)=25(51)=1275<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "stan H. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );