Blackjack is a special kind of casino game as it doesn’t have independence from hand to hand. Because a card, once left the deck, can not come back until the deck is reshuffled. It means that the previous card affects the probability of the next card, and therefore, card counting is a possible means to estimate future win potential. Consider this:
The probability of drawing a natural from a deck is
Suppose an ace is removed from the deck. The updated probability for the natural is:
Or if a three was removed,
