## Variations theory

# Variations

**Variations** is to group elements, when it matters the order, we do not take all the items and these can be repeated or not. Thus the variations may be:

__Variations without repetition of n elements__

It is called common variations of m elements taken from n in n (m = n) to different groups consisting of n elements, choosing them among the m elements that we have, so that:

– All the elements are not included.

– The order matters.

– The ítems are not repeated.

Therefore, a variation will be considered distinct from another if they differ in some element or if they are located in a different order.

__Variations with repetition of n elements__

It is called variations with repetition of m elements taken from n in n to the different groups formed by n elements such as:

– All the elements are not included if m is greater tan n. All the elements are included if m=n.

– The order matters.

– The ítems are repeated.

In this case, a variation will be considered distinct from another if they differ in any of the elements or if they are located in different order.

You can download the App BioProfe READER to practice this theory with self-corrected exercises.