The value of $$40 - \Big[ 3 - \Big\{ 4 - \Big( 6 - \overline{6 - 4} \Big) \Big\} \Big]$$​is .......

Correct option is D

​Given:

$$40 - \Big[ 3 - \Big\{ 4 - \Big( 6 - \overline{6 - 4} \Big) \Big\} \Big]$$ 

Concept Used: 

BODMAS rule:

​$$\begin{array}{|c|c|} \hline \textbf{Operation preference wise} & \textbf{Symbol} \\ \hline Brackets &[],{}, () \\ \hline Orders, of & ² (power), √ (root) , of \\ \hline Division & ÷ \\ \hline Multiplication & × \\ \hline Addition & + \\ \hline Subtraction & - \\ \hline \end{array}$$​​

Solution: 

$$40 - \Big[ 3 - \Big\{ 4 - \Big( 6 - \overline{6 - 4} \Big) \Big\} \Big] \\ \ \\ = 40 - \Big[ 3 - \Big\{ 4 - \Big( 6 - 2 \Big) \Big\} \Big] \\ \ \\ = 40 - \Big[ 3 - \Big\{ 4 - 4 \Big\} \Big] \\ \ \\ = 40 - \Big[ 3 - 0 \Big]\\ \ \\ = 40 - 3 = 37$$ ​

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