If ‘P’ stands for ‘×’, ‘Q’ stands for ‘÷’, ‘R’ stands for ‘−’ and ‘S’ stands for ‘+’ , what will come in place of the question mark ‘?’in the following equation?

(32 Q 2) P 4 R 35 S (7 P 3) S 20 R 18 Q 3 =?

Given: (32 Q 2) P 4 R 35 S (7 P 3) S 20 R 18 Q 3 =?

​$$\begin{array}{|c|c|} \hline\textbf{Operation preference wise} & \textbf{Symbol} \\\hline\text{Brackets} &[],{}, () \\ \hline \text{Orders, of} & (power), √ (root) , of \\ \hline \text{Division}& ÷ \\ \hline \text{Multiplication} & × \\ \hline \text{Addition} & + \\ \hline \text{Subtraction} & - \\\hline\end{array}$$​​

(32 ÷ 2) × 4 − 35 + (7 × 3) + 20 − 18 ÷ 3 = ?

16 × 4 − 35 + 21 + 20 − 6 = ?

64 − 35 + 21 + 20 − 6 = ?

64 + 21 + 20 - 41 = ? 

105 - 41 = ? 

Thus, the correct option is (a) 64.