((17,65-9,25)2,5-3,90,4)/2,43

First, we calculate the values inside the parentheses:

(17,65 - 9,25) = 8,4
(2,5 - 3,9) = -1,4

Next, we multiply the first result by 2,5:
8,4 * 2,5 = 21

Then, we multiply the second result by 0,4:
-1,4 * 0,4 = -0,56

Now, we subtract the second result from the first result:
21 - (-0,56) = 21 + 0,56 = 21,56

Finally, we divide the result by 2,43:
21,56 / 2,43 ≈ 8,88

Therefore, the final answer is approximately 8,88.