2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/20767A simple "trick" is proposed, which allows to perform exactly the site-averaging procedure required when developing integral equation theories of interaction site models of macromolecular fluids. It shows that no approximation is involved when the number of Ornstein-Zernike equations coupling the site-site correlation functions is reduced to one. Its potential practical interest for future theoretical developments is illustrated with a rederivation of the so-called molecular closures.2 pages, revTeX 4Soft Condensed Mattertext