5th Grade · Number & Operations in Base Ten

Add & Subtract Decimals

5.NBT.B.7

Definition

To combine or take away decimals by lining up the decimal points and place values.

Examples

  • 3.25 + 1.40 = 4.65.
  • 5.80 - 2.35 = 3.45.

Key rule

Line up the decimal points so each place value matches before adding or subtracting.

Memory hook

Line up the dots before you add or take away.