A standard deck of cards has 52 cards. The 52 cards are divided into four suits: diamonds, clubs, hearts, and spades. Diamonds and hearts are red cards, and clubs and spades are black cards. Suppose you choose a card from the deck. Let event A be you choose a red card and event B you choose an ace. Determine P(A and B) , P(A) , and P(B) , and state whether events A and B are independent. Enter the first three answers in fraction form. Reduce your answer.

P (A and B) = (answer here)
P(A) = (answer here)
P (B) = (answer here)

Enter 1 if events A and B are dependent. Enter 2 if events A and B are independent (answer here)

1 answer

To determine the probabilities and the independence of events A and B, we start by defining the events clearly:

  • Event A: Choosing a red card. There are 26 red cards in a deck (13 diamonds + 13 hearts).
  • Event B: Choosing an ace. There are 4 aces in a deck (1 in each suit).

Next, we find the intersections and individual probabilities.

1. Calculate P(A and B): Event A and B (P(A and B)): This is the probability of choosing a card that is both a red card and an ace. There are 2 red aces (Ace of Hearts and Ace of Diamonds) in the deck.

\[ P(A \text{ and } B) = \frac{\text{Number of red aces}}{\text{Total number of cards}} = \frac{2}{52} = \frac{1}{26} \]

2. Calculate P(A): P(A) is the probability of choosing a red card. There are 26 red cards out of 52 total cards.

\[ P(A) = \frac{26}{52} = \frac{1}{2} \]

3. Calculate P(B): P(B) is the probability of choosing an ace. There are 4 aces out of 52 total cards.

\[ P(B) = \frac{4}{52} = \frac{1}{13} \]

4. Check for independence: Two events A and B are independent if:

\[ P(A \text{ and } B) = P(A) \cdot P(B) \]

We calculate \(P(A) \cdot P(B)\):

\[ P(A) \cdot P(B) = \left(\frac{1}{2}\right) \cdot \left(\frac{1}{13}\right) = \frac{1}{26} \]

Since \(P(A \text{ and } B) = P(A) \cdot P(B)\), the events A and B are independent.

Now, summarizing the results:

\[ P(A \text{ and } B) = \frac{1}{26} \] \[ P(A) = \frac{1}{2} \] \[ P(B) = \frac{1}{13} \] \[ \text{Enter 1 if dependent, 2 if independent:} \quad 2 \]

Final answers:

  • \( P(A \text{ and } B) = \frac{1}{26} \)
  • \( P(A) = \frac{1}{2} \)
  • \( P(B) = \frac{1}{13} \)
  • Independence: \( 2 \)