Exam 5: Discrete Probability Distributions

Twenty-five percent of all resumes received by a corporation for a management position are from females. Fifteen resumes will be received tomorrow. a.What is the probability that exactly 5 of the resumes will be from females? b.What is the probability that fewer than 3 of the resumes will be from females? c.What is the expected number of resumes from women? d.What is the variance of the number of resumes from women?

Two percent of the parts produced by a machine are defective. Twenty parts are selected at random. Use the binomial probability tables to answer the following questions. a.What is the probability that exactly 3 parts will be defective? b.What is the probability that the number of defective parts will be more than 2 but fewer than 6? c.What is the probability that fewer than 4 parts will be defective? d.What is the expected number of defective parts? e.What is the variance for the number of defective parts?

The expected value of a random variable is

A production process produces 2% defective parts. A sample of five parts from the production process is selected. What is the probability that the sample contains exactly two defective parts?

The hypergeometric probability distribution is identical to

Which of the following is not a property of a binomial experiment?

Variance is

An insurance company has determined that each week an average of nine claims are filed in their Atlanta branch. What is the probability that during the next week a.exactly seven claims will be filed? b.no claims will be filed? c.less than four claims will be filed? d.at least eighteen claims will be filed?

An experiment consists of determining the speed of automobiles on a highway by the use of radar equipment. The random variable in this experiment is a

The probability distribution for the rate of return on an investment is a.What is the probability that the rate of return will be at least 10%? b.What is the expected rate of return? c.What is the variance of the rate of return?

Exhibit 5-10 The probability distribution for the number of goals the Lions soccer team makes per game is given below. -Refer to Exhibit 5-10. What is the probability that in a given game the Lions will score no goals?

Exhibit 5-11 A local bottling company has determined the number of machine breakdowns per month and their respective probabilities as shown below: -Refer to Exhibit 5-11. The probability of no breakdowns in a month is

Twenty percent of the applications received for a particular position are rejected. What is the probability that among the next fourteen applications, a.none will be rejected? b.all will be rejected? c.less than 2 will be rejected? d.more than four will be rejected? e.Determine the expected number of rejected applications and its variance.

A measure of the average value of a random variable is called a(n)

Exhibit 5-4 Forty percent of all registered voters in a national election are female. A random sample of 5 voters is selected. -Refer to Exhibit 5-4. The probability that there are no females in the sample is

General Hospital has noted that they admit an average of 8 patients per hour. a.What is the probability that during the next hour less then 3 patients will be admitted? b.What is the probability that during the next two hours exactly 8 patients will be admitted?

The expected value for a binomial probability distribution is

In a large corporation, 65% of the employees are male. A random sample of five employees is selected. Use the Binomial probability tables to answer the following questions. a.What is the probability that the sample contains exactly three male employees? b.What is the probability that the sample contains no male employees? c.What is the probability that the sample contains more than three female employees? d.What is the expected number of female employees in the sample?

Exhibit 5-13 Oriental Reproductions, Inc. is a company that produces handmade carpets with oriental designs. The production records show that the monthly production has ranged from 1 to 5 carpets. The production levels and their respective probabilities are shown below. -Refer to Exhibit 5-13. the expected monthly production level is

X is a random variable with the probability function: f(X) = X/6 for X = 1, 2 or 3 The expected value of X is