Direct Proportion (or Direct Variation) Posted on 7th November 20156th July 2021 by ThePD (The Project Definition) Direct Proportion (or Direct Variation) is the relation between two quantities such that their ratio is a constant value. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Technology and tagged mathematics, science, technology. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.