Decimal separator facts for kids
The decimal separator is a special symbol that helps us understand numbers. It shows where the whole part of a number ends and the fractional part begins. Think of it as a fence between whole numbers and parts of numbers.
This symbol can be a period ("."), like in the United States and other English-speaking countries. Or, it can be a comma (","), which is common in many European countries. People often call these symbols the decimal point or decimal comma.
For example, if you see 9.5 in English-speaking countries, it means "nine and a half." But in many European countries, the same number would be written as 9,5. It's the same amount, just written differently!
Contents
What is a Decimal Separator?
A decimal separator is a small mark that divides a number into two main parts. On the left side of the separator, you have the whole number. On the right side, you have the fraction or decimal part. This part shows amounts smaller than one whole.
Why Do We Need It?
Imagine you have a pizza. If you say you ate "one five" of a pizza, it's confusing. Did you eat 15 whole pizzas? Or one and a half? The decimal separator makes it clear. If you write 1.5 pizzas, everyone knows you mean one whole pizza and half of another. It helps us write very exact numbers, like measurements or money.
Different Symbols Around the World
The two most common decimal separators are the period and the comma.
- The Decimal Point ( . ): This is used in countries like the United States, the United Kingdom, Canada, Australia, and many parts of Asia.
- The Decimal Comma ( , ): This is used in most of Europe, South America, and some parts of Africa and Asia.
It's important to know which symbol is used in different places. This helps avoid confusion, especially when dealing with international information or money.
How Numbers are Grouped
Sometimes, numbers have many digits, like 1000000. To make them easier to read, we often use a "thousands separator." This is a different symbol that groups digits in threes.
Thousands Separators
The thousands separator is not the same as the decimal separator. It helps you quickly see how big a number is.
- In countries using the decimal point, the comma (,) is often the thousands separator (e.g., 1,000,000).
- In countries using the decimal comma, a period (.) or a space is often the thousands separator (e.g., 1.000.000 or 1 000 000).
The internationally recommended way to group digits is to use a space, like 1 000 000. This avoids confusion with both decimal points and commas.
History of Decimal Separators
People have used different ways to show decimal parts for a long time. Early mathematicians tried various methods.
Early Ideas
Before decimal separators became common, people used different ways to show fractions. Some used special symbols or wrote fractions as words. As math became more advanced, a clearer system was needed.
The Rise of the Point and Comma
The use of the period and comma as decimal separators became popular over time. Different regions adopted different symbols, leading to the systems we see today. For example, in 1839, some British prints used a middle dot (·) as a decimal separator. This shows how the system has changed over the years.
Images for kids
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Three ways to group the number ten thousand with digit group separators. 1) Space, the internationally recommended thousands separator. 2) Period (or full stop), the thousands separator used in many non-English speaking countries. 3) Comma, the thousands separator used in most English-speaking countries.
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The interpunct (·) used as a decimal separator in a British print from 1839
See also
In Spanish: Separador decimal para niños
