To solve this, we will first simplify within the parentheses:

3 3/4:3 = 15/4:3 = (15/4) / 3 = (15/4) * (1/3) = 15/12 = 5/4

86,45:24 = 86.45/24 = 3.60208

Now, we will plug these values back into the original expression:

12-13/20 - (5/4 + 3.60208 + 7) * 2 2/5

First, let's simplify the parentheses:

5/4 + 3.60208 + 7 = 5/4 + 36.0208/10 + 70/10 = 15/12 + 36.0208 + 70 = 36.7708

Now, we plug the simplified value back into the expression:

12 - 13/20 - 36.7708 * 2 2/5

Next, simplify the multiplication:

36.7708 * 2 = 73.5416

Now, let's calculate 2 2/5 as an improper fraction:

2 2/5 = 5*2 + 2 / 5 = 12/5

Now, simplify the expression:

12 - 13/20 - 73.5416 * 12/5

Perform the multiplication:

73.5416 * 12/5 = 176.09984

Now, let's simplify the final expression:

12 - 13/20 - 176.09984

Convert 13/20 to a decimal:

13/20 = 0.65

Now calculate the final result:

12 - 0.65 - 176.09984 ≈ -164.75

Therefore, the final result is approximately -164.75.