\item A box contain six tickets, numbered as shown:\medskip

\hspace*{140pt}\begin{picture}(126,11)(0,5)
\put(0,0){\line(0,1){18}}
\put(0,0){\line(1,0){124}}
\put(124,0){\line(0,1){18}}
\put(06,6){\fbox{1}}
\put(26,6){\fbox{2}}
\put(46,6){\fbox{3}}
\put(66,6){\fbox{4}}
\put(86,6){\fbox{5}}
\put(106,6){\fbox{6}}\end{picture}\medskip

Three tickets are drawn at random, without replacement, from the box. Find the chance the three tickets left in the box are 4, 5, and 6.
