[1] Mayobre received a doctorate from Central University of Venezuela, in economic and social sciences, 1944, and in law, 1945.
Upon returning to his country in 1946, Mayobre worked in the Central Bank of Venezuela's Department of Economic Research and became its director.
He joined the United Nations Secretariat in 1951 as the Delegated Director of ECLAC's subregional headquarters in Mexico.
Then, in 1953, he was appointed Resident Representative of the United Nations' Technical Assistance Board in Central America.
He returned to Venezuela to direct the Corporación Venezolana de Comercio (Venezuelan Trade Corporation).