Frequency is a termed used in mathematics to determine the number of occurrences for a particular event during an instance of time. By dividing the number of events by the unit of time, you can find the frequency. In elementary school, frequency is usually determined by counting the number of tally marks for a given area. It is a term often used when analyzing a data table or graph. Thus, frequency is related to the area of probability and data analysis.
Calculating Frequency I: General

Find the category for the event that you need to find the frequency for.

Count the number of events for a particular category. Each tally represents an event in the chosen category. For example, in the following data identifying the types of pets the students have, the frequency of cats is 6: Dogs: IIIIIIII, Cats: IIIIII, Fish: IIII.

Repeat the preceding steps to find the frequencies for the other categories. In the previous example, the frequency of dogs is 8, and the frequency of fish is 4.
Calculating Frequency II: One Unit of Time

Determine the number of units. For example, if 8 waves reached the shore during observation, the number of events is 8.

Determine the length of time. For example, if your observations lasted four minutes, 4 minutes is the length of time.

Divide the number of events by the amount of time. For example, if there are 8 waves in 4 minutes, 8 / 4 = 2. Two is the frequency of waves reaching the shore per minute.
Tips & Warnings
 Frequency = Events / Time
References
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