document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=208032>Question 208032</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Could someone tell me if I understood this right? I should find out if these are geometric (if then I should give the common ratio) or arithmetic (if then I should give the common difference) <BR>\n" );
document.write( "Are these right; <BR>\n" );
document.write( "8,12,16,20... are Geometric with ratio=4 <BR>\n" );
document.write( "3,-6,12,-24...are geometric with ratio=-3<BR>\n" );
document.write( "8,11,13,15... are none of both<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 #157341 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=157341\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Are these right; <BR>\n" );
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document.write( "FIRST SEQUENCE<BR>\n" );
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document.write( "8,12,16,20...<BR>\n" );
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document.write( "this one is arithmetic with common difference = 4<BR>\n" );
document.write( "12 - 8 = 4<BR>\n" );
document.write( "16 - 12 = 4<BR>\n" );
document.write( "20 - 16 = 4<BR>\n" );
document.write( "8 + 4 = 12 + 4 = 16 + 4 = 20 ...<BR>\n" );
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document.write( "SECOND SEQUENCE<BR>\n" );
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document.write( "3,-6,12,-24...<BR>\n" );
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document.write( "this one is geometric with common ratio = -2 (not 3)<BR>\n" );
document.write( "-6 / 3 = -2<BR>\n" );
document.write( "12 / -6 = -2<BR>\n" );
document.write( "-24 / 12 = -2<BR>\n" );
document.write( "3 * (-2)  = -6 * (-2) = 12 * (-2) = -24 ...<BR>\n" );
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document.write( "THIRD SEQUENCE<BR>\n" );
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document.write( "8,11,13,15...<BR>\n" );
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document.write( "can't see an arithmetic sequence here.<BR>\n" );
document.write( "thought it would be 2 in an arithmetic but the first number throws it off since the difference between 11 and 8 is 3.  once it gets past 11 it seem to be a common difference of 2 but the first number is an exception unless it was really 9?<BR>\n" );
document.write( "11 - 8 = 3<BR>\n" );
document.write( "13 - 11 = 2<BR>\n" );
document.write( "15 - 13 = 2<BR>\n" );
document.write( "as it is there doesn't seem to be a common difference<BR>\n" );
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document.write( "can't see a geometric sequence here.<BR>\n" );
document.write( "11/8 = 1.375<BR>\n" );
document.write( "13/11 = 1.18181818...<BR>\n" );
document.write( "15/13 = 1.153846...<BR>\n" );
document.write( "there doesn't seem to be a common ratio<BR>\n" );
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