[QUOTE="Nuckfut"] Oh dear...[/QUOTE] Now I know its you Connor- WTF? Common sense for such a calculation is a) eeeh thats about right for a tank full of petrol b) Simplify the numbers and say "about 40 quid" c) calculator out. d) back of envelope+pencil to multiply a 3 digit number with a 2 digit number is a bit of a party piece, It would be a waste of time to teach people to do such a pointless thing. There are many other more worthwhile things to do. Much as it might be an exercise to clean the kitchen floor with a toothbrush, or if you have a 3 mile trip - do it on foot, or if you have a 20 item shopping list to memorise it rather than write it down. Hardly "oh dear..." if you chose the easier and more sensible answer.