decimal point
Quick Summary
The decimal point is a symbol, typically a period or a comma, used in mathematics to separate the whole number part of a number from its fractional part. It is a key component of the decimal system, which is a base-10 positional numeral system using digits 0 through 9.12
A decimal fraction is a fraction where the denominator is a power of 10, often expressed using a decimal point. For example, 0.25 represents 25/100. The placement of the decimal point is crucial for determining a number's value. In the decimal system, numbers like 543.21 can be broken down by place value: (5 × 102) + (4 × 101) + (3 × 100) + (2 × 10-1) + (1 × 10-2). This system has been fundamental to Western commerce and science since its introduction to the West in the 12th century.32
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