Question 1. Max Sandlin is exploring the characteristics of stock market investors. He found that sixty percent of all investors have a net worth exceeding $1,000,000; 20% of all investors use an online brokerage; and 10% of all investors a have net worth exceeding $1,000,000 and use an online brokerage. An investor is selected randomly, and E is the event "networth exceeds $1,000,000," and O is the event "uses an online brokerage." P(O|E) = _____________.
a. 0.80
b. 0.70
c. 0.50
d. 0.17
Question 2. Suppose a committee of 3 people is to be selected from a group consisting of 4 men and 5 women. What is the probability that one man and two women are selected?
a. 0.33
b. 0.15
c. 0.06
d. 0.48
Question 3. James Desreumaux, VP of Human Resources of American First Banks (AFB), is reviewing the employee training programs of AFB banks. His staff randomly selected personnel files for 100 tellers in the Southeast Region, and determined that their mean training time was 25 hours and that the standard deviation was 5 hours. The 92% confidence interval for the population mean of training times is ________.
a. 24.30 to 25.71
b. 16.25 to 33.75
c. 24.13 to 25.99
d. 17.95 to 32.05