Exam 6: Discrete Probability Distributions

A statistics professor receives an average of five e-mail messages per day from students. Assume the number of messages approximates a Poisson distribution. What is the probability that on a randomly selected day she will have two messages?

For the following distribution: What is the mean of the distribution?

A tennis match requires that a player win three of five sets to win the match. If a player wins the first two sets,what is the probability that the player wins the match,assuming that each player is equally likely to win each set?

To construct a binomial probability distribution,the mean must be known.

For the following distribution: What is the mean of the distribution?

Which shape describes a Poisson distribution?

Which of the following is a requirement for use of the hypergeometric distribution?

Chances are 50-50 that a newborn baby will be a girl. For families with five children,what is the probability that all the children are girls?

Sweetwater & Associates write weekend trip insurance at a very nominal charge. Records show that the probability that a motorist will have an accident during the weekend and file a claim is 0.0005. Suppose they wrote 400 policies for the coming weekend,what is the probability that exactly two claims will be filed?

The following is a binomial probability distribution with n = 3 and π = 0.20. The variance of the distribution is ________.

Which of the following is NOT a characteristic of a binomial probability distribution?

A measure of the long-run average value of a random variable used to represent the central location of a probability distribution is called a(n)________.

David's gasoline station offers 4 cents off per gallon if the customer pays in cash and does not use a credit card. Past evidence indicates that 40% of all customers pay in cash. During a one-hour period,15 customers buy gasoline at this station. What is the probability that at least 10 pay in cash?

Judging from recent experience,5% of the computer keyboards produced by an automatic,high-speed machine are defective. If six keyboards are randomly selected,what is the probability that none of the keyboards are defective?

Affirmative action commitments by many organizations have led to an increase in the number of women in executive positions. Satellite Office Systems has vacancies for two executives that it will fill from among four women and six men. What is the probability that at least one woman is selected?

For the following distribution: What is the variance of the distribution?

A company is studying the number of monthly absences among its 125 employees. The following probability distribution shows the likelihood that people were absent 0,1,2,3,4,or 5 days last month. Given the probability distribution,which of the following predictions is correct?

Affirmative action commitments by many organizations have led to an increase in the number of women in executive positions. Satellite Office Systems has vacancies for two executives that it will fill from among four women and six men. What is the probability that no woman is selected?

In a large metropolitan area,past records revealed that 30% of all the high school graduates go to college. From 20 graduates selected at random,what is the probability that exactly 8 will go to college?

The following is a Poisson probability distribution with µ = 0.1. The mean of the distribution is ________.