54240:678 = 80
830/671 ≈ 1.2363
125/96 = 1.3021
73836:9 = 8204

Now we can plug these values back into the equation:

80 + 1.2363 - (1.3021 - 8204)
= 80 + 1.2363 - (-8202.6979)
= 80 + 1.2363 + 8202.6979
= 8283.9342

Therefore, 54240:678 + 830/671 - (125/96 - 73836:9) ≈ 8283.9342.