There are 52 cards in a standard deck, 26 of them are black and there are 2 black ace. Since the probability is equatl to the number of possible outcomes divided by the total number of outcomes,
[tex]P(A\cap B)=P(\text{ ACE AND BLACK)=}\frac{2}{52}[/tex]By simplyfing this result, the answer is:
[tex]P(A\cap B)=P(\text{ ACE AND BLACK)=}\frac{1}{26}[/tex]