1. **State the problem:** We want to find the conditional probability that a card drawn from a standard 52-card deck is a heart, given that the card is red.
2. **Recall the formula for conditional probability:**
$$P(A|B) = \frac{P(A \cap B)}{P(B)}$$
where $A$ is the event "card is a heart" and $B$ is the event "card is red".
3. **Identify the events:**
- Total cards: 52
- Red cards: 26 (hearts and diamonds)
- Hearts: 13
4. **Calculate $P(A \cap B)$:** Since all hearts are red, $A \cap B$ is just the event "card is a heart," so
$$P(A \cap B) = \frac{13}{52}$$
5. **Calculate $P(B)$:** Probability the card is red is
$$P(B) = \frac{26}{52}$$
6. **Apply the conditional probability formula:**
$$P(A|B) = \frac{\frac{13}{52}}{\frac{26}{52}}$$
7. **Simplify the fraction:**
$$P(A|B) = \frac{13}{52} \times \frac{52}{26} = \frac{13}{\cancel{52}} \times \frac{\cancel{52}}{26} = \frac{13}{26}$$
8. **Simplify further:**
$$P(A|B) = \frac{13}{26} = \frac{1}{2}$$
**Final answer:** The conditional probability that the card is a heart given that it is red is $\frac{1}{2}$.
Conditional Probability Db1D18
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