Depends on the length of the trip in the city. If its a regular 3 km journey to a school and back, then 10 is very generous; the car will spend most of its time with the choke applied.
On the other hand, if its a 20+ km journey on mostly on two lane boulevards, then 15+ km/l is not entirely impossible.
These figures are real life examples from my own driving experience; I used to get 8 km/l from my Cultus in my pre hypermiling days, going to school and back.
Nowadays, I have tested my with hypermiling and longer distances within city, I easily get 15 km/l from the same car; its my minimum in fact.