A number is a mathematical object used to:
Example: When we are interested in the total number of each species of tortoise, or how many individuals there are per square kilometre.
This type of data is called commonly:
The same number may be:
Number Type | Equation they help to solve |
---|---|
Negative number | a + x = b, even when a > b |
Fractions | ax = b, when b is not divisible by a |
Reals | x² = 2 |
Complex numbers | x² = -1 |
Numbers can be classified into set, called number system.
The most common number system (ie number classification) are:
Numbers can be expressed (ie written) into set, called numeral system (or system of numeration). It is a mathematical notation system for expressing numbers using digits (or other symbols).
Example of numeral system (ie number representation)]]:
Numbers can be stored in:
However, since division almost immediately introduces infinitely repeating sequences of digits (such as 4/7 in decimal, or 1/10 in binary), the representation would be:
A field is a collection of “numbers” with their operator: +, -, *, /
Quantitative variables can be further categorized as either: