Operator precedence

           When an expression contains more than one operator, the order of evaluation depends on the order of operations.

        

  The acronym PEMDAS (Parentheses, Exponentiation, Multiplication, Division, Addition, Subtraction) is a useful way to remember the rules:

            * Parentheses have the highest precedence and can be used to force an expression to evaluate in the order you want. Since expressions in parentheses are evaluated first, 2 * (3-1)is 4, and (1+1)**(5-2) is 8.You can also use parentheses to make an expression easier to read, as in (minute* 100) / 60, even if it doesn’t change the result.

            * Exponentiation has the next highest precedence, so 1 + 2**3 is 9, not 27, and 2 *3**2 is 18, not 36.
            * Multiplication and Division have higher precedence than Addition and Subtraction. So 2*3-1 is 5, not 4, and 6+4/2 is 8, not 5.
            *Operators with the same precedence are evaluated from left to right (except exponentiation).