yhteenlaskusäännön
Yhteenlaskusääntö, also known as the addition rule, is a fundamental concept in probability theory and combinatorics. It describes how to calculate the probability of the union of two events, meaning the probability that at least one of the events occurs. The rule states that the probability of event A or event B occurring is equal to the probability of A plus the probability of B, minus the probability of both A and B occurring. This can be expressed mathematically as P(A U B) = P(A) + P(B) - P(A ∩ B).
The subtraction of P(A ∩ B) is crucial because if events A and B are not mutually exclusive,
The addition rule is widely applied in various fields, including statistics, data analysis, and decision-making under