document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1007387>Question 1007387</A>: <I><SPAN STYLE=\"word-break: break-all;\"> John does 10 pushups on the first day of a 30-day month, and then increases the number of pushups by 3 pushups a day. How many pushups has he done in total by the end of the month? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #623306 by </B><A HREF=/tutors/aboutme.mpl?userid=tiffany222><B>tiffany222(56)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=tiffany222><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=623306\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To find sum of an arithmetic sequence use this formula:<BR>\n" );
document.write( "Sn = n/2 (a1 + an)<BR>\n" );
document.write( "Known information:<BR>\n" );
document.write( "n = 30, a1 = 10, d = 3<BR>\n" );
document.write( "To find an (last term of sequence), use this formula:<BR>\n" );
document.write( "an = a1 + (n-1)d<BR>\n" );
document.write( "a30 = 10 + (30-1)(3)<BR>\n" );
document.write( "a30 = 10 +87<BR>\n" );
document.write( "a30 = 97<BR>\n" );
document.write( "Substitute into sum formula:<BR>\n" );
document.write( "Sn = n/2 (a1 + an)<BR>\n" );
document.write( "S30 = 30/2 (10 + 97)<BR>\n" );
document.write( "S30 = 15(107)<BR>\n" );
document.write( "S30 = 1605\r<BR>\n" );
document.write( "\n" );
document.write( "Final Answer: 1605 pushups<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );