\[\boxed{\mathbf{107.}}\]
\[P(A \cap B) = P(B) \cdot P\left( A \middle| B \right)\]
\[P\left( A \middle| B \right) = P(A \cap B)\ :P(B);\]
\[P(B) = 0,4;\ \ P\left( A \middle| B \right) = 0,05:\]
\[P\left( A \middle| B \right) = \frac{0,05}{0,4} = \frac{5}{40} = \frac{1}{8}.\]
\[Ответ:\ \frac{1}{8}.\]