Btw, there are threads all over the web arguing this equation.
This is what a professor is saying he was taught back in the 60's.
As I remember them being taught to me, the rules giving the precedence
order for the four arithmetic operations are:
(1) all multiplication (in any order)
(2) all division, as they occur from left to right
(3) all addition and subtraction, as they occur from left to right