If you don’t see a difference between “do the tens, then do a simple subtraction with digits between 1 - 9” and dividing an arbitrary number by four, then there is no sense arguing. Also it would lead to bad results in your example - the average number of legs a sheep has isn’t 4.
And the easiest way to count sheep is to count all the legs and divide by 4, right?
If you don’t see a difference between “do the tens, then do a simple subtraction with digits between 1 - 9” and dividing an arbitrary number by four, then there is no sense arguing. Also it would lead to bad results in your example - the average number of legs a sheep has isn’t 4.
For most herds of sheep, the average is four.