document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1159888>Question 1159888</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the next number in the series 9, 11, 22, 15, 17, 34, 25, 27, 54, 43, 45, 90? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #783003 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=783003\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "The question is invalid, as suggested by the response from tutor @ikleyn; ANY next number makes a valid sequence.<br><BR>\n" );
document.write( "This kind of problem (if well formulated!) can be good for helping students look for patterns in the given numbers.  But NO MATTER HOW LOGICAL AN ANSWER YOU MIGHT FIND, you can NEVER know that it is the \"right\" answer.<br><BR>\n" );
document.write( "I recommend you look at each problem like this and try for a minute or two to find a pattern in the given numbers; but don't spend a lot of time on any such problem, because any answer you come up with is only a guess.<br><BR>\n" );
document.write( "Here are some patterns I see in these numbers....<br><BR>\n" );
document.write( "9 to 11: add 2<BR>\n" );
document.write( "11 to 22: multiply by 2<BR>\n" );
document.write( "22 to 15: ???<BR>\n" );
document.write( "15 to 17: add 2<BR>\n" );
document.write( "17 to 34: multiply by 2<BR>\n" );
document.write( "34 to 25: ???<BR>\n" );
document.write( "25 to 27: add 2<BR>\n" );
document.write( "27 to 54: multiply by 2<BR>\n" );
document.write( "54 to 43: ???<BR>\n" );
document.write( "43 to 45: add 2<BR>\n" );
document.write( "45 to 90: multiply by 2<BR>\n" );
document.write( "90 to __: ???<br><BR>\n" );
document.write( "The \"add 2, multiply by 2, and ???\" repeat in a sequence.  Figure out a pattern for the \"???\", and you will have a good GUESS for the next number.<br><BR>\n" );
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