8th Grade · The Number System
Repeating Decimal
8.NS.A.1
Definition
A decimal in which a digit or block of digits repeats infinitely. Shown with a bar over the repeating part. Repeating decimals are rational numbers.
Examples
- 0.333... is written 0.3 with a bar — the 3 repeats.
- 0.142857142857... has a 6-digit repeating block.
Key rule
Both terminating and repeating decimals are rational.
Memory hook
The bar shows what repeats forever.