Tientallen

Tientallen is a Dutch word meaning tens. It can denote a group of ten items, or, more commonly in mathematics, the tens place in a decimal number. The term is the plural of tiental, a group or set of ten, and derives from tien (ten) with the suffix -tal, used to form collective nouns. In everyday language, tientallen is also used to express approximate quantities, as in tientallen mensen (“tens of people”), tientallen euro’s, or tientallen jaren to mean decades or roughly ten-year spans.

In mathematics, tientallen are a fundamental element of the decimal system. Numbers are composed from place values: eenheden (ones), tientallen (tens), honderdtallen (hundreds), and so on. A number like 34 consists of 3 tientallen and 4 eenheden, i.e., 30 plus 4. The tens digit is obtained by floor(n/10). The word tientallen can thus refer to the set of tens in a range, for example the tientallen van 10 tot 90, or to the tens collectively as a category.

Historically, the decimal system and the concept of tens have been central to arithmetic development across many cultures. Today, tientallen remains a standard term in Dutch mathematics education and everyday language to describe quantities in blocks of ten or to talk about approximate counts.