\[1)\ P(A) = \frac{18}{36} \bullet \frac{18 - 1}{36 - 1} =\]
\[= \frac{1}{2} \bullet \frac{17}{35} = \frac{17}{70};\]
\[2)\ P(A) = \frac{18}{36} \bullet \frac{18}{36 - 1} =\]
\[= \frac{1}{2} \bullet \frac{18}{35} = \frac{18}{70};\]
\[3)\ P(A) = \frac{18}{36 - 1} = \frac{18}{35}.\]