Exam 7: Sampling and Sampling Distributions

A population has a mean of 84 and a standard deviation of 12.A sample of 36 observations will be taken.The probability that the sample mean will be between 80.54 and 88.9 is

A simple random sample of 28 observations was taken from a large population.The sample mean equaled 50.Fifty is a

In point estimation

A population of 1,000 students spends an average of $10.50 a day on dinner.The standard deviation of the expenditure is $3.A simple random sample of 64 students is taken. a.What are the expected value,standard deviation,and shape of the sampling distribution of the sample mean? b.What is the probability that these 64 students will spend a combined total of more than $715.21? c.What is the probability that these 64 students will spend a combined total between $703.59 and $728.45?

A single numerical value used as an estimate of a population parameter is known as

A sample statistic,such as a sample mean,is known as

The closer the sample mean is to the population mean,

Which of the following is(are)point estimator(s)?

A simple random sample of size n from an infinite population of size N is to be selected.Each possible sample should have

How many different samples of size 3 can be taken from a finite population of size 10?

The standard deviation of all possible Values is called the

Since the sample size is always smaller than the size of the population,the sample mean

Exhibit 7-2 A random sample of 10 examination papers in a course,which was given on a pass or fail basis,showed the following scores. -Refer to Exhibit 7-2.The point estimate for the variance of the population is

An automotive repair shop has determined that the average service time on an automobile is 2 hours with a standard deviation of 32 minutes.A random sample of 64 services is selected. a.What is the probability that the sample of 64 will have a mean service time greater than 114 minutes? b.Assume the population consists of 400 services.Determine the standard error of the mean.

From a population of 200 elements,a sample of 49 elements is selected.It is determined that the sample mean is 56 and the sample standard deviation is 14.The standard error of the mean is

In computing the standard error of the mean,the finite population correction factor is used when

A sample of 66 observations will be taken from an infinite population.The population proportion equals 0.12.The probability that the sample proportion will be less than 0.1768 is

A finite population correction factor is needed in computing the standard deviation of the sampling distribution of sample means

An experimental diet to induce weight loss was followed for one week by a randomly selected group of 12 students with the following results. a.Find a point estimate for the average amount lost after one week on this diet.Is this an unbiased estimate of the population mean? Explain. b.Find a point estimate for the variance of the amount lost on this diet.Is this an unbiased estimate of the population variance? Explain. c.Find a point estimate for the standard deviation of the amount lost on this diet.

A population characteristic,such as a population mean,is called