As part of a quality assurance program, the Customer Relations manager would like to develop ...

  

As part of a quality assurance program, the Customer Relations manager would like to develop a plant that allows him to evaluate the performance of his employees. From past experience, he knows the probability that a new emplyee will write an initial draft of a response that contains errors is approximately 10%. The manager would like to know how many of the 300 responses he should sample to have a cost-effective quality assurance program.

a) Let X be a discrete ransom variable that represents the number of the n=300 draft responses that contain errors. Describe the probability distribution for X. Be sure to include the name of the probability distribution, possible values for the random variable X, and values of the parameters

b) To be effective, the manager would like to have a 95% probability of finding at least one draft document that contains an error. If the probability that a draft document will have errors is known to be 10%, determine the appropriate sample size the satisfy the manager's requirements.