Exam 5: Discrete Probability Distributions

When a household is randomly selected, the probability distribution for the number x of cars owned is as described in the accompanying table. The mean of the probability distribution =_____ and its standard deviation = _______.

What is the following table called?

i. A binomial distribution has a characteristic that an outcome of an experiment is classified into one of two mutually exclusive categories (a success or a failure). ii. A binomial distribution has the characteristic that the probability of a success stays the same for each trial, but the probability of a failure varies from trial to trial. iii. The mean of a binomial probability distribution can be determined by multiplying the probability of a failure by the number of trials.

Belk Department Store is having a special sale this weekend. Customers charging purchases of more than $50 to the Belk credit card will be given a special Belk lottery card. The customer will scratch the card, which will indicate the amount to be taken off the total amount of purchase. Listed below is the amount of the prize and the percent of the time that amount will be deducted from the total amount of the purchase. Determine the mean and standard deviation of the prize amounts.

A multiple-choice test consists of six questions, each with A-E answers. If you guess the answer to each question, how many questions can you expect to get correct?

A multiple-choice test consists of five questions, each with A-E answers. If you guess the answer to each question, what is the probability of getting four or more questions correct?

i. For a binomial distribution, each trial has a known number of successes. For example, a four question multiple-choice test can only have zero, one, two, three and four successes (number correct). ii. To construct a binomial probability distribution, the number of trials and the probability of success must be known. Iii) A binomial distribution has a characteristic that the trials are independent, which means that the outcome of one trial does not affect the outcome of any other trial.

Which of the following is correct about a probability distribution?

Carlson Jewellers permits the return of their diamond wedding rings, provided the return occurs within two weeks of the purchase date. Their records reveal that 10 percent of the diamond wedding rings are returned. Five different customers buy five rings. What is the probability that all will be returned?

In a large metropolitan area, past records revealed that 30 percent of all the high school graduates go to college. From 10 graduates selected at random, the probability that none will go to college is_____%.

The probability that exactly ten customers will ask for hot peppers is______ .

i. As a general rule of thumb, if the items selected for a sample are not replaced and the sample size is less than 5 percent of the population, the binomial distribution can be used to approximate the hypergeometric distribution. Ii) If the probability of success does not remain the same from trial to trial when sampling is done without replacement, the hypergeometric distribution should be applied. Iii) In the hypergeometric distribution the probability of a success is not the same on each trail.

What must you know to develop a binomial probability distribution?

Elly's hot dog emporium is famous for its chilidogs. Some customers order the hot dogs with hot peppers, while many do not care for that added bit of zest. Elly's latest sales indicate that 30% of The customers ordering her chilidogs order it with hot peppers. Suppose 18 customers are selected at random. What is the probability that fifteen or more customers will want hot peppers?

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 0.00555. Suppose they wrote 400 policies for the coming weekend, how many claims could they expect to be filed?

i. The probability of a particular outcome, designated X, must always be between 0 and 1 inclusive. ii. A random variable represents the outcomes of an experiment. Iii) The mean of a probability distribution is referred to as its expected value.

Judging from recent experience, 5 percent of the computer keyboards produced by an automatic, high- speed machine are defective. What is the probability that out of six keyboards selected at random, exactly zero keyboards will be defective?

A______ random variable can assume only a certain number of separated values.

The probabilities and the number of automobiles lined up at a Lakeside Olds at opening time (7:30 a.m.) for service are: On a typical day, how many automobiles should Lakeside Olds expect to be lined up at opening?

For the hypergeometric distribution there are_______ possible outcomes.