1. **State the problem:** We need to find the probability $P(E)$ that a card drawn from a standard 52-card deck is the 3 of diamonds. 2. **Formula for probability:** The probability of an event $E$ is given by $$P(E) = \frac{\text{Number of favorable outcomes}}{\text{Total number of possible outcomes}}$$ 3. **Identify favorable outcomes:** There is exactly one 3 of diamonds in the deck. 4. **Identify total outcomes:** There are 52 cards in total. 5. **Calculate probability:** $$P(E) = \frac{1}{52}$$ 6. **Interpretation:** The probability of drawing the 3 of diamonds is $\frac{1}{52}$, which is already in simplest form.