MATHEMATICAL DISCOVERY CAN BE MADE IN SCHOOL!
Chika Ofili, a Nigerian boy, 12-year-old living
in London just discovered a new Formula for
divisibility by 7 in maths.
Multiply the last digit by 5 and add it to the remaining numbers.
For Example 532
53+2 * 5 =63 which is a multiple of 7, So 532 is divisible by 7.
Chika Ofili has been presented with a special Recognition Award for making a new discovery in mathematics
Here is a simple Proof:-
If x+5b=0 mod 7 then multiplying by 10 we get
10x+50b=0 mod 7.
But 50 is just 1 mod 7 so we get 10x+b=0 mod 7 as an equivalent statement.
Multiply the last digit by 5 and add it to the remaining numbers.
For Example 532
53+2 * 5 =63 which is a multiple of 7, So 532 is divisible by 7.
Chika Ofili has been presented with a special Recognition Award for making a new discovery in mathematics
Here is a simple Proof:-
If x+5b=0 mod 7 then multiplying by 10 we get
10x+50b=0 mod 7.
But 50 is just 1 mod 7 so we get 10x+b=0 mod 7 as an equivalent statement.
Wondering why this never clicked to me during my school days... This was fascinating
ReplyDeleteAn interesting approach indeed. Such news should be given more recognition to tell high school students that they too, are not far from discovering something new !!
ReplyDelete