A mathematical proportion is an equation that shows two ratios are equal. For example, if we have the ratio of a to b and the ratio of c to d, we can express this as a/b = c/d. Proportions are often used to solve problems involving scaling, comparisons, and relationships between quantities. Proportions can be found in various real-life situations, such as cooking, where ingredients need to be adjusted based on serving sizes. They are also essential in fields like geometry, where they help in understanding similar shapes, and in algebra, where they assist in solving equations involving unknowns.