<PRE><B>Question 1159622</B>
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As the problem is worded, &amp;nbsp;it is &amp;nbsp;UNCLEAR &amp;nbsp;if &amp;nbsp;&quot; O &quot; &amp;nbsp;can be / (or can not be) &amp;nbsp;third letter.



It depends on interpretation; &amp;nbsp;but everything that depends on interpretation --- is not a &amp;nbsp;Math problem.



It is &amp;nbsp;&quot;a puzzle&quot;, &amp;nbsp;in a bad sense of this term;  &amp;nbsp;but &amp;nbsp;NOT &amp;nbsp;a &amp;nbsp;Math problem.




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