document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=983960>Question 983960</A>: <I><SPAN STYLE=\"word-break: break-all;\"> - find the number of sides in a polygon whose interior angles are in arithmetical progression. the smallest being 120° and the common difference 5 °     </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #604892 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=604892\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> I worked this one.<BR>\n" );
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document.write( "The other tutor gave answers of 9 and 16.<BR>\n" );
document.write( "Both satisfy the equation, but 16 sides gives one angle that is 180 degs, then some that are greater than 180.<BR>\n" );
document.write( "An angle of 180 doesn't count as an angle.<BR>\n" );
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document.write( "--> only the 9 sides solution works.<BR>\n" );
document.write( "120 + 125 + 130 + 135 + 140 + 145 + 150 + 155 + 160 = 1260 --> 9 sides<BR>\n" );
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document.write( "for 16 sides,<BR>\n" );
document.write( "+ 165 + 170 + 175 + 180 ...  That's NG. </SPAN>\n" );
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