其它
When William, Mark, Diana, and Jimmy checked their book bags, they found that Mark\textquotesingle s books were fewer than Diana\textquotesingle s and Jimmy\textquotesingle s were more than William\textquotesingle s. Mark\textquotesingle s is not the least. Do you know who has the least books? (adapted from 2009 Math Kangaroo Problems, Level 1-2, Question \#21) 
Overseas Competition->Knowledge Point->Combinatorics->Logical Reasoning
Diana\textgreater Mark, so it is not Diana.  William \textless{} Jimmy, so it is not Jimmy.  We already know that Mark did not have the smallest number of books.  So, it is William. 