Placement optimisation.

hello all, sorry i am quite new at grasshopper and i have a urban design project to add public facilities in a residential area. Given that i have individual houses as points, a road network made from curves, is there a way i can calculate how many public facilities i need and their positioning if i set a rule that every house has to be within 500m from it?

in other words, the optimal position and number of new public facilities such that all houses are within 500m.

and if its not possible/too complicated, is there a method i can use to set (example) 10 new buildings and use grasshopper to identify where it would be the most optimal placement for them? 

Thanks in advance