"Problem 1
Twelve percent of all US households are in California_ A total of 1.3 percent of all US households earn more than S250,000 per year, while a total of 3.3 percent of all California households earn more than S250,000 per year.
a) What proportion of all non-California households earn more than S250,000 per 'year? b) Given that a randomly chosen US household earns more than S250,000 per year, what is the probability it is a California household?"