7th Grade · Ratios & Proportional Relationships
Percent Change
7.RP.A.3
Definition
How much a quantity increases or decreases, as a percent of the original amount.
Examples
- 20 → 25 is a +25% change
- 80 → 60 is a −25% change
Key rule
(new − old) ÷ old × 100. Divide by the ORIGINAL.
Memory hook
Difference over the original, then times 100.