A group contains 7 people. Each person’s birthday is equally likely to occur in any of the 4 seasons: Spring, Summer, Autumn, Winter. We find the probability that all four seasons occur at least once. Total Sample Space Each person has 4 choices, so total outcomes are: Favourable Outcomes (Inclusion–Exclusion) We subtract the cases where … Continue reading Probability that All Four Seasons Occur Among 7 Birthdays