A standard conditional probability answer: Randomly drawing one card, each of the 54 cards in a deck has the same probability of being drawn, i.e., 154154. Since there are 13 diamond cards, the probability of drawing a diamond card is 154∗13154∗13; there are 3 cards that are both face and diamond, so the probability of drawing such a card is 3/54. If you use the conditional probability formula for event B (drawing a card that is diamond and face) given event A (drawing a card that is a diamond),