Natural numbers are the numbers used for counting things. Natural numbers are positive numbers (numbers that are more than 0). They are 1, 2, 3, 4, 5… and so on until infinity. You can use them for counting (“there are 3 apples on the table”), and for ordering (“this is the third largest city in the country”). Mathematicians use N to refer to the set of all natural numbers:

#### N = {0, 1, 2, 3, 4, 5, 6,…}

In the decimal system each position represents a power of 10. So, beginning from the right, the first position is equivalent to 1 unit, the second one to 10 units, the third one to 100, etc. Each position gets a name according to its value.

The natural numbers can be represented on a half line (in Spanish “semirrecta”) that begins with zero and which is divided into equal segments.

To compare two numbers, we can use three symbols:

> (greater than: mayor que)

= (equal to: igual a)

< (less than: menor que)

**You can download the exercises as a pdf**

**Games**

**Download the game as a pdf**

**Crossword**

**Download the crossword as a pdf**

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