Exam 5: Discrete Distributions

A hypergeometric distribution applies to experiments in which the trials represent sampling with replacement.

If x is a binomial random variable with n=10 and p=0.8,the standard deviation of x is _________.

The following graph is a binomial distribution with n = 6. This graph reveals that ____________.

For the Poisson distribution the mean and the variance are the same.

A Poisson distribution is characterized by one parameter.

The mean or the expected value of a discrete distribution is the long-run average of the occurrences.

If x is a binomial random variable with n=10 and p=0.8,the mean value of x is _____.

Suppose that the number of calls coming per minute into an airline reservation center follows a Poisson distribution.Assume that the mean number of calls is 3 calls per minute.The probability that no calls are received in a given one-minute period is _______.

Suppose that the number of calls coming per minute into an airline reservation center follows a Poisson distribution.Assume that the mean is 3 calls per minute.The probability that at least two calls are received in a given two-minute period is _______.

On Monday mornings,customers arrive at the coffee shop drive thru at the rate of 6 cars per fifteen minute interval. Using the Poisson distribution,the probability that five cars will arrive during the next five minute interval is _____________.

If x has a binomial distribution with p = .5,then the distribution of x is ________.

A recent analysis of the number of rainy days per month found the following outcomes and probabilities. The mean of this distribution is _____________.

Dorothy Little purchased a mailing list of 2,000 names and addresses for her mail order business,but after scanning the list she doubts the authenticity of the list. She randomly selects five names from the list for validation. If 40% of the names on the list are non-authentic,and x is the number on non-authentic names in her sample,the expected (average)value of x is ______________.

Pinky Bauer,Chief Financial Officer of Harrison Haulers,Inc.,suspects irregularities in the payroll system,and orders an inspection of a random sample of vouchers issued since January 1,2006. A sample of ten vouchers is randomly selected,without replacement,from the population of 2,000 vouchers.Each voucher in the sample is examined for errors and the number of vouchers in the sample with errors is denoted by x.If 20% of the population of vouchers contain errors,P(x = 0)is _______________.

The number of cars arriving at a toll booth in five-minute intervals is Poisson distributed with a mean of 3 cars arriving in five-minute time intervals.The probability of 5 cars arriving over a five-minute interval is _______.

Suppose an interdisciplinary committee of 3 faculty members is to be selected from a group consisting of 4 men and 5 women. The probability that one male faculty and two female faculty are selected is approximately ______

In a binomial experiment,any single trial contains only two possible outcomes and successive trials are independent.

Circuit boards for wireless telephones are etched,in an acid bath,in batches of 100 boards. A sample of seven boards is randomly selected from each lot for inspection. A batch contains two defective boards; and x is the number of defective boards in the sample. P(x=1)is _______.

The number of defects per 1,000 feet of extruded plastic pipe is best modeled with the ________________.

Dorothy Little purchased a mailing list of 2,000 names and addresses for her mail order business,but after scanning the list she doubts the authenticity of the list. She randomly selects five names from the list for validation. If 40% of the names on the list are non-authentic,and x is the number of non-authentic names in her sample,P(x>0)is ______________.