But that's a theoretical calculation from the onboard trip computor not actual mpg, you will need to keep driving at 50mph without stopping and restarting to have any hope of achieving that!
Every time I fill up my van tells me I can go 650-680 miles but a mixture of cold starts and mixed driving means I will be filling up when the warning light comes on having done around 550-580 miles. If I kept driving till the tank was empty I might get 650.
Yes I know the theory is correct but it is still impressive to get 49.1 mpg
And have 820 mile left in the tank
In theory when I travel down to the south of France I should be able to get at least 43 to 40 mpg
Which is good for an aerodynamic brick