In this article, we first made an inventory of some known divisibility tests of 7 and studied their effectiveness. Then, we demonstrate a new divisibility test of 7 proposed by the young Nigerian Chika Ofili and an algorithm in #Python. Thereafter, we propose and demonstrate a new test of divisibility by 3 which we called Diouf-Pagdame Test based mainly on the calculation of d − 2e, where d and e represent, respectively, digits of tens and units of a given number. We have also emphasized the educational aspect of these methods.

divisibility test, congruence, numerations, algorithms.

Received: January 8, 2021; Accepted: January 29, 2021; Published: February 22, 2021

How to cite this article: Pagdame Tiebekabe and Ismaïla Diouf, New divisibility tests, Far East Journal of Mathematical Education 21(1) (2021), 31-41. DOI: 10.17654/ME021010031

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

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