7th Grade · Ratios & Proportional Relationships
Constant of Proportionality
7.RP.A.2
Definition
The constant ratio (k) between two proportional quantities, where y = kx.
Teach it
Where it is taught, with guided notes, practice, homework, an exit ticket and an interactive Teacher Deck.
Examples
- Table where y = 3x → k = 3
- 6 apples cost $12 → k = 2 ($ per apple)
Key rule
Find k by dividing y ÷ x for any matching pair.
Memory hook
k = y ÷ x, every single time.