I'm practicing for my EASA PPL(A) exams and one of the questions I came across looks like this:
How much taxi fuel must be consumed before take-off to reduce the aircraft mass to the maximum take-off mass?
Maximum ramp mass (MRM): 1150 kg
Actual ramp mass: 1148 kg
Maximum take-off mass (MTOM): 1145 kg (1,00 P.)
Now, my thinking was Fuel needed to be consumed = Actual ramp mass - MTOM => 3L
But it seems the correct answer is 4L. I don't understand why.