Hello!

We are very pleased to announce you our forthcoming first course of Practical Math.

It will be about the numbers and there operations. The numbers will be of progressively more and more advanced type.

These are the following, in that order:

- The positive integers to count
- The natural integers with 0, which we know on that blog that it is an important number
- The relative integers with the negative numbers, introduced by the subtraction
- The rational...