\[\boxed{\mathbf{245.}}\]
\[\textbf{а)}\ 6 + 6 + 6 = 18;\]
\[Одно\ событие.\]
\[\textbf{б)}\ 5 + 6 + 6 = 17\]
\[6 + 6 + 5 = 17\]
\[6 + 5 + 6 = 17\]
\[6 + 6 + 6 = 18\]
\[Четыре\ события.\]
\[\textbf{в)}\ 4 + 6 + 6 = 16\]
\[6 + 6 + 4 = 16\]
\[6 + 4 + 6 = 16\]
\[5 + 5 + 6 = 16\]
\[6 + 5 + 5 = 16\]
\[5 + 6 + 5 = 16\]
\[5 + 6 + 6 = 17\]
\[6 + 6 + 5 = 17\]
\[6 + 5 + 6 = 17\]
\[6 + 6 + 6 = 18\]
\[Десять\ событий.\]