Ok, so you burned through about 7 gallons of gas to drive about 62 miles. (converted to US numbers since I don't like metric
).
Roughly 8.86miles per gallon. Yeah, I'd say something isn't right.
How much idling time was there in the 100km?
How much stop-light racing did you do in the 90% city driving?
What RPM did you typically shift gears?
All of those areas will drop your gas mileage (even in a v6) pretty quickly.