👉 Pigeonholes, also known as pigeonhole principle or pigeonhole set theory, is a mathematical concept that states that in any group of $n$ objects, there must be at least one object which is not together with all others. This principle is often used to solve problems where the number of elements in a set exceeds its cardinality. For example, consider the following scenario: you have 10 apples and 5 oranges. If you randomly pick two fruits, what is the probability
