It stands for Parentheses, Exponents, Multiplication, Division, Addition, and then Subtraction. Using that method, the solution is easy.

Slide rules can perform the basic arithmetic operations of addition, subtraction, multiplication, and division, but they can also be marked for computing with logarithms, square and cube roots, ...

How to Beat Rule 9 in the Password Game First of all, in order to beat Rule 9, you need to understand that the Roman numerals are a numeral system that originated in ancient Rome.