QNT 561 FINAL EXAM – QUESTION AND ANSWERS
• A market researcher is interested in determining the average income for families in San Mateo County,
... [Show More] California. To accomplish this, she takes a random sample of 300 families from the county and uses the data gathered from them to estimate the average income for families of the entire county. This process is an example of
o Inferential statistics
• If x is a binomial random variable with n=10 and p=0.8, what is the probability that x is equal to 4?
o .0055
• The number of bags arriving on the baggage claim conveyor belt in a 3 minute time period would best be modeled with the _________.
o Poisson distribution
• According to the central limit theorem, for samples of size 64 drawn from a population with µ = 800 and σ = 56, the standard deviation of the sampling distribution of sample means would equal _______.
o 7
• Suppose a population has a mean of 400 and a standard deviation of 24. If a random sample of size 144 is drawn from the population, the probability of drawing a sample with a mean less than 402 is _______.
o 0.8413
• If x is a binomial random variable with n=10 and p=0.8, the mean value of x is _____.
o 8
• According to the central limit theorem, for samples of size 64 drawn from a population with µ = 800 and σ = 56, the mean of the sampling distribution of sample means would equal _______.
o 800
• Completion time (from start to finish) of a building remodeling project is normally distributed with a mean of 200 work-days and a standard deviation of 10 work-days. To be 99% sure that we will not be late in completing the project, we should request a completion time of _______ work-days.
o 223
• A researcher wants to determine the sample size necessary to adequately conduct a study to estimate the population mean to within 5 points. The standard deviation of population values is 80 and the researcher plans to use a 90% level of confidence. The [Show Less]