10 (ten) is the
even natural number
In mathematics, the natural numbers are the numbers 0, 1, 2, 3, and so on, possibly excluding 0. Some start counting with 0, defining the natural numbers as the non-negative integers , while others start with 1, defining them as the positive in ...
following
9 and preceding
11. Ten is the base of the
decimal numeral system, the most common system of denoting
numbers in both spoken and written language.
Name
The number "ten" originates from the
Proto-Germanic
Proto-Germanic (abbreviated PGmc; also called Common Germanic) is the linguistic reconstruction, reconstructed proto-language of the Germanic languages, Germanic branch of the Indo-European languages.
Proto-Germanic eventually developed from ...
root "*tehun", which in turn comes from the
Proto-Indo-European
Proto-Indo-European (PIE) is the reconstructed common ancestor of the Indo-European language family. No direct record of Proto-Indo-European exists; its proposed features have been derived by linguistic reconstruction from documented Indo-Euro ...
root "*dekm-", meaning "ten". This root is the source of similar words for "ten" in many other
Germanic languages
The Germanic languages are a branch of the Indo-European languages, Indo-European language family spoken natively by a population of about 515 million people mainly in Europe, North America, Oceania, and Southern Africa. The most widely spoke ...
, like
Dutch,
German, and
Swedish. The use of "ten" in the
decimal system is likely due to the fact that humans have ten
fingers and ten
toes, which people may have used to count by.
Linguistics
* A collection of ten items (most often ten years) is called a
decade.
* The
ordinal adjective is ''decimal''; the distributive adjective is ''denary''.
* Increasing a quantity by one
order of magnitude is most widely understood to mean multiplying the quantity by ten.
* To reduce something by one tenth is to ''
decimate''. (In ancient Rome, the killing of one in ten soldiers in a cohort was the punishment for cowardice or mutiny; or, one-tenth of the able-bodied men in a village as a form of retribution, thus causing a labor shortage and threat of starvation in agrarian societies.)
Mathematics
* 10 is a
composite number
A composite number is a positive integer that can be formed by multiplying two smaller positive integers. Accordingly it is a positive integer that has at least one divisor other than 1 and itself. Every positive integer is composite, prime numb ...
, the second squarefree
semiprime, the fourth
triangular number, and a
happy number.
* 10 is the smallest
noncototient number.
* There are exactly 10
small Pisot numbers that do not exceed the
golden ratio
In mathematics, two quantities are in the golden ratio if their ratio is the same as the ratio of their summation, sum to the larger of the two quantities. Expressed algebraically, for quantities and with , is in a golden ratio to if
\fr ...
.
Decagon
A ten sided polygon is called a
decagon.
List of basic calculations
Science
* The
metric system
The metric system is a system of measurement that standardization, standardizes a set of base units and a nomenclature for describing relatively large and small quantities via decimal-based multiplicative unit prefixes. Though the rules gover ...
is based on the number 10, so converting units is done by adding or removing zeros (e.g. 1
centimetre = 10
millimetres, 1
decimetre = 10 centimetres, 1
meter = 100 centimetres, 1
dekametre = 10 meters, 1
kilometre
The kilometre (SI symbol: km; or ), spelt kilometer in American English, American and Philippine English, is a unit of length in the International System of Units (SI), equal to one thousand metres (kilo- being the SI prefix for ). It is the ...
= 1,000 meters).
* The 10th
element of the
periodic table
The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows (" periods") and columns (" groups"). It is an icon of chemistry and is widely used in physics and other s ...
is
neon.
* The 10th
transition metal is
zinc.
Mysticism
In
Pythagoreanism, the number 10 played an important role and was symbolized by the
tetractys.
See also
*
*
List of highways numbered 10
Notes
References
External links
{{DEFAULTSORT:10 (Number)
Integers