How do you solve problems on parity?

To solve problems on parity, first determine the parity of the numbers involved, which can be either even or odd. You can use the properties of addition and multiplication: the sum of two even or two odd numbers is even, while the sum of an even and an odd number is odd. Similarly, the product of two even numbers or two odd numbers is even, while the product of an even and an odd number is odd. Analyzing these properties helps in forming equations or inequalities that can be solved based on the given conditions of the problem.