You will be accustomed to buying by dozens or half a dozen, for example, you will have noticed that if you are going to buy Dining set, the seller will ask you the following question: For 6 or 12 people? Covered cutlery set and so with a thousand things, that is the custom, no one has heard buy for tens or nobody sells by tens.
That has its explanation, and has to do with the origin of the numbering systems, you will have heard of the base numbering systems 2, base 3, and so other systems whose base is any number, but the one we use at the level currently is the base 10 numbering system. Let's see an example with the following number
3567 = 3x 〖10〗 ^ 3 + 5x 〖10〗 ^ 2 + 6x10 + 7, in base 10, this means that the number can be written as follows: Why, well, if you take out your account, we have 3x 〖10〗 ^ 3 + 5x 〖10〗 ^ 2 + 6x10 + 7 = 3x1000 + 5x100 + 6x10 + 7 = 3000 + 500 + 60 + 7 = 3567, a Teacher would tell you, well is that the 3 corresponds to the units of 1000, the 5 to the 100, the 6 corresponds to the wings of 10 and finally 7 corresponds to the units, and that is correct.
This can be done with any number in another system, which would change would be the base, in other articles could continue explaining this; But we return to the question that we ask, the answer to the question raised has its explanation in the following; since it turns out that before the system numbering base 10, there was the base 12 (Duodecimal System) whose origin was linked to the calculation with the Fingers, for this was taken as a reference the 12 phalanges of the 4 fingers of the hand except for the thumb, using the twelve for different units and measures is inheritance that we left that practice, is a lag that remains in time, And we still talk about in length measures like the foot (measure of English length) that are equivalent to 12 inches.
If you liked the article, vote, and if you want me to explain the other systems let me know through a message.
Image taken from