\normalsize \begin{eqnarray} P(X=4) \ &=& \ P(\mbox{male and then male and then male and then female}) \\\vspace{5} \\&=& \ P(\mbox{male} ) \times P(\mbox{male} ) \times P(\mbox{male} ) \times P(\mbox{female} ) \\\vspace{5} \\&=& \ (0.41)(0.41)(0.41)(0.59) \\\vspace{5} \\&=& \ 0.04066339 \end{eqnarray}