Refer to figure.
The maximum allowable take-off mass is the lower of:

1. RTOM: 76 000 kg
2. MLM + Trip Fuel: 66 360 + 4 761 = 71 121 kg

However, the commander wants to climb directly to the optimum altitude of FL370, so the take-off mass may be further limited by the graph.

Using the graph:

1. Start at 37 000 ft on the vertical axis and move horizontally until you reach the LRC 0.79 M line.
2. From this intersection, move vertically down to the horizontal axis to read the corresponding Brake Release Weight, which is approximately 68 000 kg.

Therefore, although the structural/performance limit is 71 121 kg, the graph limits the take-off mass to 68 000 kg if the aircraft is to climb directly to FL370.

The minimum block fuel is 8 000 kg, therefore:

Take-off fuel = Block fuel − Taxi fuel = 8 000 − 240 = 7 760 kg

Finally:

Extra Fuel = Maximum Take-off Mass − (Actual Zero Fuel Mass + Take-off Fuel) = 68 000 − (59 031 + 7 760) = 1 209 kg