500
According to a survey of American households, the probability that the residents own 2 cars if annual household income is over $25,000 is 80%. Of the households surveyed, 60% had incomes over $25,000 and 70% had 2 cars. The probability that the residents of a household own 2 cars and have an income over $25,000 a year is:
P(A/B) = P(AnB)/P(B) where:
P(A/B) = The probability of event A occurring given that B has occurred.
P(AnB) = The probability of both events A and B occurring.
P(B) = Obviously, the probability that event B occurs.
P(A) = The probability that the residents of a household own 2 cars.
P(B) = The probability that the annual household income is greater than $25,000.
P(A/B) = 0.8
P(A) = 0.7, P(B) = 0.6.
0.6*0.8 = 0.48