We are drawing two cards without replacement from a standard 52-card deck. Find the probability that we draw at least one black card.

Step 1 ：We are drawing two cards without replacement from a standard 52-card deck. We need to find the probability that we draw at least one black card.

Step 2 ：The total number of ways to draw two cards from a deck of 52 cards is given by the combination formula \(C(n, r) = \frac{n!}{(n-r)!r!}\), where n is the total number of items, and r is the number of items to choose. In this case, n = 52 and r = 2. So, the total number of ways to draw two cards is 1326.

Step 3 ：The total number of ways to draw two black cards from a deck of 26 black cards (since a standard deck has 26 black cards) is given by the same combination formula, with n = 26 and r = 2. So, the total number of ways to draw two black cards is 325.

Step 4 ：The total number of ways to draw one black card and one red card is given by the product of the number of ways to draw one black card from 26 and the number of ways to draw one red card from 26, which is \(C(26, 1) * C(26, 1)\). So, the total number of ways to draw one black and one red card is 676.

Step 5 ：The probability of drawing at least one black card is then given by the sum of the probabilities of drawing two black cards and drawing one black and one red card, divided by the total number of ways to draw two cards. So, the probability is approximately 0.7549.

Step 6 ：Final Answer: The probability that we draw at least one black card is approximately \(\boxed{0.7549}\).