A researcher in Nairobi has randomly 900

interviewed individuals in the city centre. The

following are the data he obtained: 420 were

employed by companies, 300 were self-

employed and 540 were still searching for jobs.

Of these, 180 were employed by

companies and self-employed at the same time,

120 were self-employed and still looking

other jobs, while 180 were employed by companies

and looking for other jobs. 60

individuals said they are in neither of the three categories.