document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1172339>Question 1172339</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 51 57 63 ? 75 what's the missing number of the question mark?\r<BR>\n" );
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document.write( "And this one \r<BR>\n" );
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document.write( "10 ? 24 28 30 again the missing number of the question mark please </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #797355 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=797355\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\">\r\n" );
document.write( "                     51  57  63  ?  75\r\n" );
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document.write( "difference:             6   6   ?  ?\r\n" );
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document.write( "Try difference of 6, and see what happens.\r<BR>\n" );
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document.write( "63, 69, 75\r<BR>\n" );
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document.write( "Missing number is 69. </SPAN>\n" );
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