When writing a rational number in decimal notation, a group of digits that repeats in the decimal part of the number.
Symbol
In the decimal notation of a rational number, the notation of the period p consists of drawing a line over the sequence of numbers that repeats.
In the decimal notation of the rational number \(\dfrac {22} {7}\) = 3.142 857 142 857 14 …, the period is 142 857.
\(\dfrac {22} {7} = 3.\overline {142\space857}\) and we write: p = 142 857.
Examples
- \(\dfrac{5}{3}\) = 1.666 666 666 … = 1.\(\overline {6}\) and we write: p = 6.
- If the rational number is one decimal number, the period is 0.
\(\dfrac{7}{5}\) = 1.4 and we write: p = 0.