The probability of an event is the number of outcomes that you are looking for over the total number of possible outcomes. In this case, there are four jacks and four 6s, so the total number of ways you can pick two of these together is 4 * 4 = 16 (using the multiplication rule). You also know that there are 52 cards in a deck and that you are picking with replacement, so there are a total of 52 * 52 = 2704 possible ways you an pick 2 cards (using the multiplication rule). When you divide the number of outcomes that you are looking for by the total number of outcomes, you get 16 / 2704 = 0.005917
