document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1005333>Question 1005333</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The 2nd and 5th terms of a Geometric Progression are 7 and 56 respectively . (a) find the common ratio . (b) the first term . (c) sum of the first 5 terms </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #621630 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=621630\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> An=A1*r^(n-1)<BR>\n" );
document.write( "7=A1r<BR>\n" );
document.write( "56=A1r^4<BR>\n" );
document.write( "56=8A1r<BR>\n" );
document.write( "therefore<BR>\n" );
document.write( "8A1r=A1r^4<BR>\n" );
document.write( "divide by A1 then divide by r<BR>\n" );
document.write( "8=r^3<BR>\n" );
document.write( "r=2 common ratio<BR>\n" );
document.write( "first term is 7/2 or 3.5<BR>\n" );
document.write( "sum of the first five terms <BR>\n" );
document.write( "S=A1(1-r^n)/(1-r)<BR>\n" );
document.write( "=3.5(1-2^5)(-1)<BR>\n" );
document.write( "=3.5*31=108.5<BR>\n" );
document.write( "terms are 3.5,7,14,28,56=108.5<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );