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In the course of man’s evolution, questions have been raised about how to assess the population of a herd, the production of a crop, the size of a property, the days that separate him from an event, the sharing of an inheritance … He put in place the tools of enumeration and the rules of calculation. Numbers and operations form the basis of mathematical language.

Four elementary operations translate the notions "I have more", "I have less", "I repeat", "I share". A mathematical operation associates numbers (operands) with a mathematical sign (the operator): +, -, ×, ÷. A mathematical operation involves collections of objects (or quantities) of the same nature.

- To exploit different meanings of addition, subtraction, multiplication and division with collections of objects.
- To represent natural numbers in different ways: associate a number with a set of objects.
- To introduce the commutative or non-commutative property of operations.

**Addition concept:****Addition** means to gather collections of objects of the same nature. The result of the addition is called the **sum**, it corresponds to the enumeration of all the objects…