5th Grade · Number & Operations in Base Ten
Expanded Form
5.NBT.A.3a
Definition
A number written as the sum of the values of its digits.
Examples
- 342.5 = 300 + 40 + 2 + 0.5.
- 1,809 = 1,000 + 800 + 0 + 9.
Key rule
Each addend shows one digit's true place value.
Memory hook
Break the number apart, place by place.