👉 In mathematics, a non-terminating decimal number is one that does not end in a whole number. This means that it will repeat indefinitely without a finite or repeating pattern. For example: 1/3 = 0.333... 2/5 = 0.4 These examples show that the decimal representation of fractions with denominator less than 1, such as 1/3 and 2/5, do not terminate (they continue infinitely).