Well, one suspects there might be a few extra charges (all amounts in Pond Sterling):
Booking Fee: 20
Credit card Fee: 10
Check-in Fee: 13,75
Bag Fee: 45 per bag (let's assume you'll be carrying only one)
Seat-allocation Fee: 35
Boarding Fee: 8
That's 64,75 so far.
Fuel Surcharge: 200
Bringing us to 264,75
Food: 50
Drinks: 35
IFE: 25
Head-sets: 10
TV-Guide: 5
We're now up to 391,75. Add a tenner for the ticket, and you might as well hunt for a bargain on BA or VS!