One card is drawn from a standard deck. What is the probability of drawing a heart or a spade?

1. A deck holds four suits in equal numbers, so the probability of a heart is 1/4 and the probability of a spade is also 1/4. 2. No card is both a heart and a spade, so the two events are mutually exclusive. 3. With no overlap the probabilities simply add: 1/4 + 1/4. 4. That gives 1/2. 5. Subtracting an intersection here would be an error, since the intersection is empty. _Source: OpenStax Algebra and Trigonometry (CC BY 4.0), Ch 13 "Sequences, Probability and Counting Theory", section 13.7 Probability_