Exam 4: Introduction to Probability

A production process has been producing 10% defective items. A sample of three items is selected from the production process. What is the probability that all three items are defective?

A method of assigning probabilities which assumes that the experimental outcomes are equally likely is referred to as the

Events A and B are mutually exclusive with PA) = 0.3 and PB) = 0.2. Then, PBc) =

A student has to take 7 more courses before she can graduate. If none of the courses are prerequisites to others, how many groups of three courses can she select for the next semester?

A company plans to interview 10 recent graduates for possible employment. The company has three positions open. How many groups of three can the company select?

If a six sided die is tossed two times and "3" shows up both times, the probability of "3" on the third trial is

A very short quiz has one multiple choice question with five possible choices a, b, c, d, e) and one true or false question. Assume you are taking the quiz but do not have any idea what the correct answer is to either question, but you mark an answer anyway. a. What is the probability that you have given the correct answer to both questions? b. What is the probability that only one of the two answers is correct? c. What is the probability that neither answer is correct? d. What is the probability that only your answer to the multiple choice question is correct? e. What is the probability that you have only answered the true or false question correctly?

From a group of six people, two individuals are to be selected at random. How many possible selections are there?

Assume your favorite football team has 2 games left to finish the season. The outcome of each game can be win, lose or tie. The number of possible outcomes is

A corporation has 15,000 employees. Sixty-two percent of the employees are male. Twenty-three percent of the employees earn more than $30,000 a year. Eighteen percent of the employees are male and earn more than $30,000 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 $30,000 a year? c. If an employee is taken at random, what is the probability that the employee is male and earns more than $30,000 a year? d. If an employee is taken at random, what is the probability that the employee is male or earns more than $30,000 a year? e. The employee taken at random turns out to be male. Compute the probability that he earns more than $30,000 a year. f. Are being male and earning more than $30,000 a year independent?

Two events with nonzero probabilities

Records of a company show that 15% of the employees have only a high school diploma H), 75% have bachelor degrees B), and 10% have graduate degrees G). Of those with only a high school diploma, 12% hold management positions; whereas, of those having bachelor degrees, 58% hold management positions. Finally, 82% of the employees who have graduate degrees hold management positions. a. What percentage of employees holds management positions? b. Given that a person holds a management position, what is the probability that she/he has a graduate degree?

The sample space refers to

If two events are independent, then

If A and B are independent events with PA) = 0.4 and PB) = 0.25, then PA ∪ B) =

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

Six applications for admission to a local university are checked, and it is determined whether each applicant is male or female. How many sample points exist in the above experiment?

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 are 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 lives in the dormitory, what is the probability that she/he is from Tennessee?

If A and B are independent events with PA) = 0.35 and PB) = 0.20, then, PA ∪ B) =

Of the last 100 customers entering a computer shop, 25 have purchased a computer. If the classical method for computing probability is used, the probability that the next customer will purchase a computer is