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?
9 P 9 R (7 P 3) S 24 R 6 P 2 = ?

 Given:

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?

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

9 P 9 R (7 P 3) S 24 R 6 P 2 = ?

After interchanging we get following equation - 
9 × 9 - (7  × 3) + 24 - 6 × 2 = ?
81 - 21 + 24 - 12 = ?

105 - 33
72 = ?

Correct answer is (b) 72.
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