To solve the expression \( 209,57 - 1845,69 \div ((81,3 - 78,5) \times (4,2 + 2,85)) \), we follow the order of operations.
Calculate \( 81,3 - 78,5 \): \[ 81,3 - 78,5 = 2,8 \]
Calculate \( 4,2 + 2,85 \): \[ 4,2 + 2,85 = 7,05 \]
Multiply the results from step 1 and step 2: \[ (2,8) \times (7,05) = 19,8 \]
Now divide \( 1845,69 \) by the result from step 3: \[ 1845,69 \div 19,8 \approx 93,1 \]
Finally, subtract this result from \( 209,57 \): \[ 209,57 - 93,1 \approx 116,47 \]
So, the final result is approximately: \[ \boxed{116,47} \]