A recent survey was conducted of the 30 largest public companies in a

A recent survey was conducted of the 30

largest public companies in a particular country. Of these 30

companies, 6 were banking or investment companies based in city X. A total of

12 city X companies were on the top

30 list. Suppose we select one of these

30 companies at random. Given that the company is based in city X, what is the probability that it is a banking or investment company? 
(Round to three decimal places as needed.)