7th Grade · Ratios & Proportional Relationships
Percent Decrease
7.RP.A.3
Definition
A percent change where the amount goes down from the original.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
Examples
- 50 → 40 is a 20% decrease
- $80 marked down $20 → 25% decrease
Key rule
(decrease ÷ original) × 100.
Memory hook
Went down — decrease over original.