> I can only assume that people regard 100 km as a nice base value for trip > planning, using a quick mental calculation. > > If a trip is between 400 km and 500 km and the car uses 9 L/100 km, then > it > will consume between 36 L and 45 L on the trip. The advantage is that the > trip consumption is of the same order of magnitude as the specified rate > of consumption.
Yes that is an advantage if an approximation is acceptable. An exact answer needs an initial division of the distance. Most plausible scenarios are: Your journey is 264 km, how much fuel will you use? You have 41 litres of fuel, how far can you go? One of the things that we haven't mentioned is that this measure and the imperial equivalent are inverted relative to each other. If you drive less efficiently metric numbers increase and imperial numbers decrease. This is an additional difficulty for transition. Is it better to have litres on the top or on the bottom? In any case, km/L would be a much simpler calculation. -- Terry Simpson Human Factors Consultant [EMAIL PROTECTED] www.connected-systems.com Phone: +44 7850 511794
