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.

(2 points)
P(A and B)=;
P(A)=;
P(B)=;
Enter 1 if events A and B are dependent. Enter 2 if events A and B are independent

1 answer

To solve this problem, we first need to find the probabilities of events A and B, and then check for independence.

  1. Determine \( P(A \text{ and } B) \):
    • Event A is choosing a red card. There are 26 red cards (13 diamonds + 13 hearts) in the deck.
    • Event B is choosing an ace. There are 4 aces total (one in each suit).
    • The intersection \( A \text{ and } B \) (choosing a card that is both red and an ace) includes the two red aces: the Ace of Diamonds and the Ace of Hearts. So, there are 2 outcomes that are both in A and B.

\[ P(A \text{ and } B) = \frac{\text{Number of favorable outcomes for } A \text{ and } B}{\text{Total number of outcomes}} = \frac{2}{52} = \frac{1}{26} \]

  1. Determine \( P(A) \):
    • As mentioned, there are 26 red cards.

\[ P(A) = \frac{\text{Number of favorable outcomes for } A}{\text{Total number of outcomes}} = \frac{26}{52} = \frac{1}{2} \]

  1. Determine \( P(B) \):
    • There are 4 aces in total.

\[ P(B) = \frac{\text{Number of favorable outcomes for } B}{\text{Total number of outcomes}} = \frac{4}{52} = \frac{1}{13} \]

  1. Check for Independence:
    • Two events A and B are independent if \( P(A \text{ and } B) = P(A) \times P(B) \).

Calculating \( P(A) \times P(B) \):

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

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

Therefore, the answers are:

  • \( P(A \text{ and } B) = \frac{1}{26} \)
  • \( P(A) = \frac{1}{2} \)
  • \( P(B) = \frac{1}{13} \)
  • Events A and B are independent, so enter 2.

Final answers:

  • \( P(A \text{ and } B) = \frac{1}{26} \)
  • \( P(A) = \frac{1}{2} \)
  • \( P(B) = \frac{1}{13} \)
  • Events A and B are independent: 2.