document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1195934>Question 1195934</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The second and seventh term of a GP are 18 and 4374 respectively. Find the first term </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #828563 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=828563\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> geometric progression formula is An = a * r^(n-1)<BR>\n" );
document.write( "when n = 2, the formula becomes A2 = a * r^1 = 18<BR>\n" );
document.write( "when n = 7, the formula becomes A7 = a * r^6 = 4374<BR>\n" );
document.write( "a is the first term in the progression.<BR>\n" );
document.write( "solve for a in both terms 2 and 7 to get:<BR>\n" );
document.write( "a = 18/r^1<BR>\n" );
document.write( "a = 4374/r^6<BR>\n" );
document.write( "since they both equal a, set the terms equal to each other to get:<BR>\n" );
document.write( "18/r^1 = 4374/r^6<BR>\n" );
document.write( "multiply both sides of the equation to r^6 and divide both sides of the equation by 18 to get:<BR>\n" );
document.write( "r^6/r^1 = 4374/18<BR>\n" );
document.write( "simplify the left side of the equation to get:<BR>\n" );
document.write( "r^5 = 4374/18<BR>\n" );
document.write( "take the fifth root of both sides of the equaion to get:<BR>\n" );
document.write( "r = (4374/18)^(1/5)<BR>\n" );
document.write( "solve for r to get:<BR>\n" );
document.write( "r = 3.<BR>\n" );
document.write( "when A2 = 18, the formula becomes:<BR>\n" );
document.write( "18 = a * 3^1 = 18 = a * 3<BR>\n" );
document.write( "divide both sides of the equation by 3 to get:<BR>\n" );
document.write( "18/3 = a = 6.<BR>\n" );
document.write( "when A7 = 4374, the formula becomes:<BR>\n" );
document.write( "4374 = a * 3^6<BR>\n" );
document.write( "solve for a to get:<BR>\n" );
document.write( "a = 4374/3^6 = 6.<BR>\n" );
document.write( "a is the first term in the formula which is equal to 6.<BR>\n" );
document.write( "that's your solution.<BR>\n" );
document.write( " </SPAN>\n" );
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