Directions: In this type you are provided with substitutes for various mathematical symbols or numerals, followed by a question involving calculation of an expression or choosing the correct / incorrect equation. You are required to put in the real signs or numerals in the given equation and then solve the question.

If P denotes ÷, Q denotes ×, R denotes + and S denotes -, then what is the value of 18 Q 12 P 4 R 5 S 6?