Exam 7: Sampling and Sampling Distributions

According to the central limit theorem,for samples of size 169 drawn from a population with  = 1,014 and  = 65,the mean of the sampling distribution of sample means would equal _______.

Catherine Chao,Director of Marketing Research,needs a sample of households to participate in the testing of a new toothpaste package.She directs the seven members of her staff to find five households each.Catherine's sample is a _____________.

On Saturdays,cars arrive at David Zebda's Scrub and Shine Car Wash at the rate of 80 cars per hour during the ten-hour shift.David wants a sample of 40 Saturday customers to answer the long version of his quality service questionnaire.He randomly selects 9 as a starting point and instructs the crew to select the 9th customer and each customer at intervals of 20 (9,29,49,etc.).His sample is a __________.

Suppose 65% of all college students have a laptop computer at home and a sample of 150 is taken.The standard deviation of the sampling distribution of is

According to the central limit theorem,for samples of size 64 drawn from a population with  = 800 and  = 56,the mean of the sampling distribution of sample means would equal _______.

Abel Alonzo,Director of Human Resources,is exploring employee absenteeism at the Harrison Haulers Plant.Abel knows that absenteeism varies significantly between departments.For example,workers in the wood shop are absent more than those in the tuning department and the size of the departments ranges from 40 to 120 workers.He orders a random sample of 10% of the workers from each of the six departments.Abel's sample is a ________________.

According to the central limit theorem,if a sample of size 56 is drawn from a population with a standard deviation of 14,the standard deviation of the distribution of the sample means would equal _______.

According to the central limit theorem,for samples of size 169 drawn from a population with  = 1,014 and  = 65,the standard deviation of the sampling distribution of sample means would equal _______.

The mean of the sample means is the same as the mean of the population

Abel Alonzo,Director of Human Resources,is exploring employee absenteeism at the Harrison Haulers Plant.Abel knows that absenteeism varies significantly between departments.For example,workers in the wood shop are absent more than those in the tuning department and the size of the departments ranges from 40 to 120 workers.He orders a random sample of 10 workers from each of the six departments.Abel's sample is a ________________.

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 of more than 404.5 is _______.

If every unit of the population has the same probability of being selected to the sample,then the researcher is probably conducting random sampling.

Pinky Bauer,Chief Financial Officer of Harrison Haulers,Inc.,suspects irregularities in the payroll system.If 10% of the 5,000 payroll vouchers issued since January 1,2000,have irregularities,the probability that Pinky's random sample of 200 vouchers will have a sample proportion greater than .06 is ___________.

Suppose 40% of the population of pre-teens have a TV in their bedroom.If a random sample of 500 pre-teens is drawn from the population,then the probability that between 36% and 44% of the pre-teens have a TV in their bedroom is _______.

Suppose the population of all public Universities shows the annual parking fee per student is $110 with a standard deviation of $18.If a random sample of size 49 is drawn from the population,the probability of drawing a sample with a mean of more than $115 is _______.

Catherine Chao,Director of Marketing Research,needs a sample of Kansas City households to participate in the testing of a new toothpaste package.If 40% of the households in Kansas City prefer the new package,the probability that Catherine's random sample of 300 households will have a sample proportion between 0.35 and 0.45 is ___________.

Albert Abbasi,VP of Operations at Ingleside International Bank,is evaluating the service level provided to walk-in customers.Accordingly,he plans a sample of waiting times for walk-in customers.Albert randomly selects 4 as a starting point and instructs his staff to record the waiting times for the 4th walk-in customer and every 10th customer thereafter (4,14,24,etc.).Albert's sample is a ________.

According to the central limit theorem,if a sample of size 56 is drawn from a population with a mean of 16,the mean of all sample means would equal _______.

A random sample of size 100 is drawn from a population with a standard deviation of 10.If only 5% of the time a sample mean greater than 20 is obtained,the mean of the population is ______

The sampling distribution of the sample means is less variable than the population distribution.