document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=72205>Question 72205</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the missing geometric sequence   15, __ , 81,...<BR>\n" );
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document.write( "Find the missing geometric sequence   36, __ , 100, ... <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #51604 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=51604\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the missing geometric sequence 15, __ , 81,...<BR>\n" );
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document.write( "If it's a geometric sequence there must be a \"common ratio\" \"r\" between<BR>\n" );
document.write( "the terms.<BR>\n" );
document.write( "So the terms are 15, 15r,(15r)r<BR>\n" );
document.write( "Thus 15r^2=81<BR>\n" );
document.write( "r^2=81/15<BR>\n" );
document.write( "r=9/sqrt15<BR>\n" );
document.write( "So the missing element is 15(9/sqrt15) = 9sqrt15<BR>\n" );
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document.write( "Find the missing geometric sequence 36, __ , 100, ... <BR>\n" );
document.write( "Following the same argument as above:<BR>\n" );
document.write( "36r^2=100<BR>\n" );
document.write( "r^2=100/36<BR>\n" );
document.write( "r=10/6 = 5/3<BR>\n" );
document.write( "Therefore the missing term is 36(5/3)=60<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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