What can factorials be used for in real life?

Answer 1

Factorials involve repeated multiplication of all integers up to a limit specified. they are denoted by an exclamation mark. For example, 5! = 5 x 4 x 3 x 2 x 1 = 120.

In real life, they are an important part of combinatorics. For example, how many different ways can you order a list of people? This is the simplest application, and is simply K!, K being the number of people. This is extended to how many different ways can you choose N people from a group of K? This is applied using the binomial coefficient, written as nCk, where n is the number of people you need and k is the people you can choose from (hence it is called "n-choose-k" for simplicity).

Other applications include advanced algebra in sequences and series, in calculus for similar reasons, in probability, in number theory and in several other areas of study. Like many other aspects of mathematics, they are also advanced and applied to areas outside their normal use and this can be used to develop and/or solve some very complex equations.

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