Understanding Permutations with an Example

In this class, We discuss Understanding Permutations with an Example.

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Permutations:

Several ways we can make arrangements are called permutations.

Example:

Given five alphabets: A, B, C, D, and E.

How many different words are possible with given alphabets?

Solution:

Some of the arrangements are shown below.

A B C D E

A B C E D

E A B C D

The five alphabets are placed in five different positions.

_ _ _ _ _

The first position can be filled in five possible ways.

We fill the first position with A.

A _ _ _ _

The second position can be filled in four possible ways.

Point to understand: The first two positions can be filled in 5*4 possible ways.

Why 5 * 4?

The diagram below shows you why the multiplication is.

The five alphabets are filled in five positions in 5! Ways.

5 * 4 * 3* 2* 1

= 120 ways

The number of words possible is 120.