Exam 4: Introduction to Probability

The probability of an intersection of two events is computed using the

Sixty percent of the student body at UTC is from the state of Tennessee (T), 30% percent are from other states (O), and the remainder is international students (I). Twenty percent of students from Tennessee live in the dormitories, whereas 50% of students from other states live in the dormitories. Finally, 80% of the international students live in the dormitories. a.What percentage of UTC students live in the dormitories? b.Given that a student lives in the dormitory, what is the probability that she/he is an international student? c.Given that a student does not live in the dormitory, what is the probability that she/he is an international student?

If P(A) = .6, P(B) = .3, and P(A $\cap$ B) = .2, then P(B|A) =

An experiment consists of three steps. There are four possible results on the first step, three possible results on the second step, and two possible results on the third step. The total number of experimental outcomes is

When the assumption of equally likely outcomes is used to assign probability values, the method used to assign probabilities is referred to as the

A corporation has 15,000 employees. Sixty-two percent of the employees are male. Twenty-three percent of the employees earn more than $40,000 a year. Eighteen percent of the employees are male and earn more than $40,000 a year. a. If an employee is taken at random, what is the probability that the employee is male? b. If an employee is taken at random, what is the probability that the employee earns more than $40,000 a year? c. If an employee is taken at random, what is the probability that the employee is male and earns more than $40,000 a year? d. If an employee is taken at random, what is the probability that the employee is male or earns more than $40,000 a year or both? e. The employee taken at random turns out to be male. Compute the probability that he earns more than $40,000 a year. f. Are being male and earning more than $40,000 a year independent?

A graphical device used for enumerating sample points in a multiple-step experiment is a

On a December day, the probability of snow is .30. The probability of a "cold" day is .50. The probability of snow and a "cold" day is .15. Are snow and "cold" weather independent events?

In a random sample of UTC students 50% indicated they are business majors, 40% engineering majors, and 10% other majors. Of the business majors, 60% were females; whereas, 30% of engineering majors were females. Finally, 20% of the other majors were female. a.What percentage of students in this sample was female? b.Given that a person is female, what is the probability that she is an engineering major?

If A and B are mutually exclusive, then

Which of the following statements is(are) always true?

An experiment consists of four outcomes with P(E₁) = 0.2, P(E₂) = 0.3, and P(E₃) = 0.4. The probability of outcome E₄ is

A statistics professor has noted from past experience that a student who follows a program of studying two hours for each hour in class has a probability of 0.9 of getting a grade of C or better, while a student who does not follow a regular study program has a probability of 0.2 of getting a C or better. It is known that 70% of the students follow the study program. Find the probability that if a student who has earned a C or better grade, he/she followed the program.

If A and B are independent events with P(A) = 0.38 and P(B) = 0.55, then P(A|B) =

If P(A) = 0.80, P(B) = 0.65, and P(A $\cup$ B) = 0.78, then P(B|A) =

Super Cola sales breakdown as 80% regular soda and 20% diet soda. Men purchase 60% of the regular soda, but only 30% of the diet soda. If a woman purchases Super Cola, what is the probability that it is a diet soda?

Posterior probabilities are computed using

A method of assigning probabilities based upon judgment is referred to as the

If a penny is tossed three times and comes up heads all three times, the probability of heads on the fourth trial is

A graphical method of representing the sample points of a multiple-step experiment is