First up you need to look at which is the limiting weight.
PLTOM 66300 PLLM 55200 MZFM 53070
PLTOM = 66300
PLLM 55200 + trip fuel 8600 = 63800
MZFM 53070 + Take off fuel 10900 = 63970
From the above we can see that the PLTOM is the most limiting at 63800.
Next we need to find out the landing fuel
DOM 34900 + Traffic 16600 = 51500
To find out the landing fuel
PLTOM 55200 - 51500 = 3700.
So we land with 3700 on board. Next we add the trip fuel of 8600 this will give us 12300.
NOW REMEMBER The question asks how much fuel can be loaded PRIOR to departure..i.e. on the RAMP..So we include the Taxi fuel of 400
12300 + 400 = 12700