\[1)\ P(A) = \frac{70}{90} \bullet \frac{70 - 1}{90 - 1} = \frac{7}{9} \bullet \frac{69}{89} =\]
\[= \frac{483}{801} = \frac{161}{267}.\]
\[Ответ:\ \ \frac{161}{267}.\]
\[2)\ P(A) = \frac{70}{90 - 1} = \frac{70}{89}.\]
\[Ответ:\ \ \frac{70}{89}.\]