The word “relative” is used to indicate that an event is being considered in relation or in proportion to something else. A relative frequency indicates how often a specific kind of event occurs within the total number of observations. It is a frequency that uses percentages, proportions and fractions. In this sub-topic, we will learn how to calculate relative frequency.

Relative frequency of an event can be defined as the number of times an event occurs divided by the total number of events occurring in a given trials.

We can take the relative frequency of an event occurring as an estimate of the probability of that event occurring. The estimate improves as the number of trials is increased.

Suppose that we make n trials and that r of those trials are success, then, based on this evidence, an estimate for the probability of success or outcomes favorable to event E in the experiment is given by:

Relative frequency calculations convert counts into percentages by taking the count of a specific type of event and dividing it by the total number of observations.