Arranging the group of elements in a order is known as Permutation.
suppose we have three letters x, y and z. For each one letters can be written in 3 different ways. The first, second or third letter can be written in 3 possible ways, as shown in figure below.

Permutations and Combinations



Selecting and arranging a group of elements in an interval of time is known as Combinations.
Suppose we have four numbers 5, 6, 7 and 8. It can be arranged in 1 way when order does not matter.
This Online Calculator helps us to learn more about Permutations and Combinations and solve the given problems.
Below you could see Permutations and Combinations formula

Permutation formula is P(n, r) = $\frac {n!}{(n-r)!}$
Where n is number of elements and r is number of times.

Combinations formula is C(n, r) = $\frac {n!}{(r!(n-r)!)}$

Where n is number of elements and r is number of times.

Factorial is a positive integer and it is denoted with the symbol 'n!'. It is a product of positive integer 1 to n.

    0! = 1
    n! = $1 \times 2 \times 3 ...\times n$