Lawrence Hall of Science
The Math Page: Skill in Arithmetic: Proportionality
Acquire a deeper understanding of the concept of proportionality. Concise definitions, detailed examples, and an interactive worksheet to apply what you have learned.
CK-12 Foundation
Ck 12: Algebra: Ratio, Proportion, and Variation
[Free Registration/Login may be required to access all resource tools.] Understand direct and inverse variation.