3G,
Having spent a wee bit of time on the 777 over the last few years, one statistic I always trotted out to visitors was that the triple carries 2/3rds the pax load of a 744, can carry them further than a 744, with around half the fuel burn per hour. (6 to 7 tonnes to be precise.) Pretty impressive economics.
Should help. Good luck at final board, any more questions feel free to e-mail me privately and I'll do my best, but can't promise!
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