The concept of an interval-valued Fermatean fuzzy set (IVFFS). an extension of Fermatean fuzzy sets. is a more resilient and reliable tool for dealing with uncertain and incomplete data in practical applications. The purpose of this paper is to define a triangular interval-valued Fermatean fuzzy number (TIVFFN) and its arithmetic operations. https://www.diariolahumanidad.com/product-category/cesti/