Maths really isn't my strong point haha. But what you said lastly sounds correct for me tbh. As sometimes I can get 300 miles off half a tank so that working out at 50MPG is actaully quite good.
Even getting 280 will probabaly be round 46/47MPG then?
And so now I reckon I am doing 40 - 50 MPG or even closer to 45 - 50MPG
Quite surprised actually. Thanks for that mate