From a standard 52-card deck, what is the probability of drawing a red card?

Introduction / Context:
A standard deck has equal numbers of red and black cards, making this a symmetry-based probability.

Given Data / Assumptions:

• Standard deck: 52 cards.
• Red suits: hearts and diamonds (26 cards total).

Concept / Approach:
P(red) = number of red cards / total cards = 26 / 52.

Step-by-Step Solution:
Probability = 26/52 = 1/2.

Verification / Alternative check:
P(black) = 26/52 = 1/2; the two are complementary and sum to 1.

Why Other Options Are Wrong:
1/13 corresponds to a specific rank in a suit; 1/4 is a single suit; 2/18 is nonsensical for a 52-card deck.

Common Pitfalls:
Confusing suit probabilities (1/4) with colour probabilities (1/2).

Final Answer:
1/2