A standard deck of has 52 cards, and contains 13 cards of each of the four suits: diamonds, spades, hearts, and clubs. What is the probability that you choose a spade, given that you have already chosen a diamond (and have not replaced it)?

Answer 1

so have a diamond, which means there are 51 cards left, of which 13 are still spades

Prob(spade) = 13/51