Exam 5: Discrete Distributions

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 contains errors,the standard deviation 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 contains errors,the mean value of x is __________.

The number of successes in a hypergeometric distribution is unknown

To compute the variance of a discrete distribution,it is not necessary to know the mean of the distribution.

A student randomly guesses the answers to a five question true/false test. If there is a 50% chance of guessing correctly on each question,what is the probability that the student misses no questions?

A market research team compiled the following discrete probability distribution on the number of sodas the average adult drinks each day. In this distribution,x represents the number of sodas which an adult drinks. The mean (average)value of x is _______________.

Epsilon Manufacturing Company makes a specialized electronic product used in the automotive industry.This product has 4 components,each of which could be defective.So the total number of defects of this product can be 0,1,2,3,or 4.The following table provides the probabilities of the number of defects: The standard deviation of the number of defects is _______.

One hundred policyholders file claims with CareFree Insurance. Ten of these claims are fraudulent. Claims manager Earl Evans randomly selects four of the one hundred claims for thorough investigation. If x represents the number of fraudulent claims in Earl's sample,x has a _______________ distribution.