`140 div [61 - {36 - (40 - 60 div 12 xx 6)}] = ?`

Options

A. 2
B. 5
C. 4
D. 10

Answer

To solve the expression \( 140 \div [61 - \{36 - (40 - 60 \div 12 \times 6)\}] \), we will follow the BODMAS/BIDMAS rule, which stands for Brackets, Orders (i.e., powers and square roots, etc.), Division and Multiplication (from left to right), Addition and Subtraction (from left to right).

### Step-by-Step Solution:

1. **Identify the innermost bracket**: Start with the round bracket \( (40 - 60 \div 12 \times 6) \).

- **Hint**: Always start with the innermost brackets first.

2. **Calculate \( 60 \div 12 \)**:
\[ 60 \div 12 = 5 \]

- **Hint**: Division is performed before multiplication in the absence of brackets.

3. **Now substitute back into the round bracket**:
\[ 40 - 5 \times 6 \]

- **Hint**: Replace the division result back into the expression.

4. **Calculate \( 5 \times 6 \)**:
\[ 5 \times 6 = 30 \]

- **Hint**: Perform multiplication next.

5. **Now substitute back into the round bracket**:
\[ 40 - 30 = 10 \]

- **Hint**: After calculating multiplication, perform the subtraction.

6. **Now substitute back into the curly bracket**:
\[ 36 - 10 = 26 \]

- **Hint**: Continue substituting results back into the expression.

7. **Now substitute back into the square bracket**:
\[ 61 - 26 = 35 \]

- **Hint**: Again, replace the calculated value into the expression.

8. **Now we have the expression**:
\[ 140 \div 35 \]

- **Hint**: You are now left with a simple division.

9. **Calculate \( 140 \div 35 \)**:
\[ 140 \div 35 = 4 \]

- **Hint**: Perform the final division to get the answer.

### Final Answer:
The result of the expression \( 140 \div [61 - \{36 - (40 - 60 \div 12 \times 6)\}] \) is \( 4 \).