A 12-year-old Nigerian has made history after making a new discovery in the field of Mathematics.
Chika Ofili, who is based in the UK, was awarded over the weekend at the TruLittle Hero Awards for discovering the new formula for divisibility by seven in mathematics.
Ofili’s teacher, Miss Mary Ellis, who is also the head of the Mathematics department at Westminster Under School said he discovered the formula while solving a holiday assignment. Miss Ellis said in an educational journal that she gave a book called First Steps for Problem Solvers (published by the UKMT) to study during the holidays.
The book had several divisibility tests that used to quickly work out whether a number is exactly divisible by either 2, 3, 4, 5, 6, 7, 8 or 9 before you start dividing. The book had no memorable test listed for checking divisibility by 7.
Ofili, however, discovered the formula and had an algebraic proof to back it up.
The new formula involves taking the last digit of any whole number, multiply it by 5 and then add it to the remaining part of the number to get a new number. If this new number is divisible by 7, then the original number is divisible by 7.