\[\boxed{\mathbf{55.}}\]
\[\textbf{а)}\ \ \overline{А} = орел\ выпадет\ один\ \]
\[раз\ и\ более.\]
\[Р\left( \ \overline{А} \right) = 1 - \frac{1}{16} = \frac{15}{16}.\]
\[\textbf{б)}\ \ \overline{А} = орел\ выпадет\ не\ более\ \]
\[одного\ раза.\]
\[Р\left( \ \overline{А} \right) = \frac{1}{16} + \frac{1}{4} = \frac{1}{16} + \frac{4}{16} = \frac{5}{16}.\]
\[\textbf{в)}\ \ \overline{А} = орел\ выпадет\ не\ менее\ \]
\[трех\ раз.\]
\[Р\left( \ \overline{А} \right) = \frac{1}{4} + \frac{1}{16} = \frac{5}{16}.\]
\[\textbf{г)}\ \ \overline{А} = орел\ выпадет\ \]
\[точно\ 2\ раза.\]
\[Р\left( \ \overline{А} \right) = \frac{3}{8}.\]