Simplify :
`10-[8-{11+30div(4-overline(5-7))}]`

Answer

To simplify the expression `10 - [8 - {11 + 30 ÷ (4 - (5 - 7))}]`, we will follow the order of operations (parentheses, exponents, multiplication and division from left to right, addition and subtraction from left to right).

### Step-by-Step Solution:

1. **Evaluate the innermost parentheses:**
\[ 5 - 7 = -2 \]
Now, substitute this back into the expression:
\[ 10 - [8 - {11 + 30 ÷ (4 - (-2))}] \]

2. **Evaluate the expression in the parentheses next:**
\[ 4 - (-2) = 4 + 2 = 6 \]
Substitute this back into the expression:
\[ 10 - [8 - {11 + 30 ÷ 6}] \]

3. **Now, perform the division:**
\[ 30 ÷ 6 = 5 \]
Substitute this back into the expression:
\[ 10 - [8 - {11 + 5}] \]

4. **Now, simplify inside the curly brackets:**
\[ 11 + 5 = 16 \]
Substitute this back into the expression:
\[ 10 - [8 - 16] \]

5. **Now, simplify inside the square brackets:**
\[ 8 - 16 = -8 \]
Substitute this back into the expression:
\[ 10 - (-8) \]

6. **Now, simplify the final expression:**
\[ 10 + 8 = 18 \]

### Final Answer:
The simplified value of the expression is **18**.