(840 300 - 567 846)+(3 427 546-300 928)=

To solve the expression \((840300 - 567846)+(3427546 - 300928)\), we will calculate each part step-by-step.

1. Calculate \(840300 - 567846\): \[ 840300 - 567846 = 272454 \]

2. Calculate \(3427546 - 300928\): \[ 3427546 - 300928 = 3126618 \]

3. Now add the two results together: \[ 272454 + 3126618 = 3399072 \]

So, the final result is: \[ \boxed{3399072} \]