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Decimal Number System

An animated hand counting to five.  Source: Microsoft.An animated hand counting to five.  Source: Microsoft.

The Decimal number system has a base of 10. Therefore, the 10 digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 are used. (Remember if you know the number systems base you can determine how many digits it uses).

What happens when the ten single digits are exceeded? To write the value 10 we have to represent it by using two digits. To write the value 100 we have to represent it by using three digits, hence the use of multiple digits to represent higher and higher values. Each of these subsequent digits is associated with a place value (This place value is also known as a weighting factor). Each place value or weighting factor is associated with a power of ten.

105 104 103 102 101 100
Hundreds of Thousands Tens of Thousands Thousands Hundreds Tens Ones
100000 10000 1000 100 10 1


Notice from the table above how the powers of ten get progressively larger the further to the left we go.

Next: Binary Number System