Which one of the following formulae is used for computing the aedes aegypti index at international airpos and sea po-

Aedes aegypti index is defined as the ratio expressed as a percentage between the number of houses in a limited well-defined area on the premises of which actual breeding of Aedes aegypti are found and the total number of houses examined in that area Park's Textbook of Preventive and Social Medicine, 25th Edition, Pg