2. What is decimal? The decimalnumeral system (also called base ten or occasionally denary) has ten as its base. It is the most widely used numeral base. A Decimal Number (based on the number 10) contains a Decimal Point.
3. Place Value To understand decimal numbers you must first know about Place Value. When we write numbers, the position (or "place") of each number is important. In the number 327: the "7" is in the Units position, meaning just 7 (or 7 "1"s), the "2" is in the Tens position meaning 2 tens (or twenty), and the "3" is in the Hundreds position, meaning 3 hundreds.
4. Decimal Point The decimal point is the most important part of a Decimal Number. It is exactly to the right of the Units position. Without it, we would be lost ,,, and not know what each position meant. Now we can continue with smaller and smaller values, from tenths, to hundredths, and so on, like in this example:
5. Large and Small So, our Decimal System lets us write numbers as large or as small as we want, using the decimal point. Numbers can be placed to the left or right of a decimal point, to indicate values greater than one or less than one. For example: 17.591 The number to the left of the decimal point is a whole number (17 for example) As we move further left, every number place gets 10 times bigger.
6. The first digit on the right means tenths (1/10). As we move further right, every number place gets 10 times smaller (one tenth as big).
7. Decimal fractions Decimal fractions are commonly expressed without a denominator, the decimal separator being inserted into the numerator (with leading zeros added if needed), at the position from the right corresponding to the power of ten of the denominator. e.g., 8/10, 83/100, 83/1000, and 8/10000 are expressed as: 0.8, 0.83, 0.083, and 0.0008. In English-speaking and many Asian countries, a period (.) or raised period (•) is used as the decimal separator; in many other countries, a comma is used.
