twelve percent of all us households are in california a tota

twelve percent of all us households are in california. a total of 3.3 percent of all us households earn over 250000 per year, while a total of 63 percent of california households earn over 250000 per year. if a randomly chosen us household earns over 250000 per year what is the probability it is from california?

Solution

Say we have 1000 households in all

12% * 1000 = 120 households in California

3.3 percent of all us households earn over 250000 per year :
Total number of households earning more than 250 grand : 3.3% of 1000 = 33

6.3 percent of california households earn over 250000 per year
Total number of households earning more than 250 grans in Cali = 6.3% of 120 = 7.56

It is given that the household chosen is one of the 33 that earn more than 250000

So, P(california) = 7.56 / 33 * 100 = 22.91% approx

NOTE : I believe the 63% was a misprint, So i went with 6.3% instead, please comment on this answer if you have any doubts