Count the number of cards that you can see. For example, if there are three communal cards and you can see the two cards in your hand, you know five cards.
Subtract the number of cards you know from 52, the number of cards in the deck, to find the number of possible cards. Do not include cards you cannot see, such as the cards in your opponents hand. For this example, since you know five cards, subtract 5 from 52 to get 47.
Subtract the number of queens you can see from four, the number of queens in the deck. For example, if you can see one queen, subtract 1 from 4 to find there are three queens remaining in the deck.
Subtract the number of queens remaining in the deck from the number of possible cards to find the number of non-queen cards. In this example, subtract 3 from 47 to find there are 44 cards that are not queens.
Divide the number of non-queen cards by the total number of possible cards left in the deck to find the probability the card is not a queen. In this example, divide 44 by 47 to find the probability the card is not a queen equals 0.9362, or about 93.62 percent.