(3.5 - 8) * 2.7 + 2.5 : (3 - 11 во второй степени) * 5

Let's solve the expression step by step:

1. Calculate the term inside the first parentheses:
   \[ 3.5 - 8 = -4.5 \]

2. Multiply this result by 2.7:
   \[ -4.5 * 2.7 = -12.15 \]

3. Calculate the term inside the second parentheses:
   \[ 3 - 11^2 = 3 - 121 = -118 \]

4. Now multiply this by 5:
   \[ -118 * 5 = -590 \]

5. Now divide 2.5 by the result obtained in step 4:
   \[ 2.5 : -590 = \frac{2.5}{-590} = -\frac{2.5}{590} = -\frac{1}{236} \]

6. Now we can combine the two results from steps 2 and 5:
   \[ -12.15 - \frac{1}{236} \]

To add these two numbers, we can convert -12.15 to a fraction:
\[ -12.15 = -\frac{1215}{100} \]

Finding a common denominator (which is 23600) allows us to add:
\[ -\frac{1215 \times 236}{23600} - \frac{100}{23600} = -\frac{287340 + 100}{23600} = -\frac{287440}{23600} \]

So, the final result of the expression is: \[ -\frac{287440}{23600} \] This fraction can be simplified if needed. However, the exact numerical answer would be approximately \( -12.15 - 0.0042 \approx -12.1542 \).

Would you like me to further simplify it or provide additional insights?