sampling distribution of the mean definition

Which of the following is a property of sampling distribution? I. Mean of sampling distribution equals population mean. II. Sample mean comes closer to population mean than any other unbiased mean. I..

What formula is used to gain information about a sample mean when the variable is normally distributed or when the sample size is 30 or more? => z = X - μ σ or z = X ‾ - μ σ n or z = X ‾ - μ σ n or z = X - μ &sigm..

Select the incorrect statement(s). I. A sampling distribution of sample means is a distribution obtained by using the means computed from random samples of a specific size taken from a population. II. Sampling error is ..

A population consists of the five numbers 1, 3, 5, 7 and 9. Consider all the samples of size 2 that can be drawn without replacement from the population. Find the mean and the variance of the sampling distribution means. => 6 and 4.05 or 6 and 3 or ..

A central office operator has observed that the long distance telephone calls are normally distributed with a mean of 6 minutes and a standard deviation of 2 minutes. If random samples of 32 calls were selected, what is the probability that the length of the sampl..

As the sample size n increases without limit, the shape of the distribution of the sample means taken with replacement from a population with mean μ and standard deviation σ will approach a normal distribution. This distribut..

Assume that the weights of 3,000 students at a university are normally distributed with mean 150 pounds and a standard deviation of 2.72 pounds. How many samples would you expect to find the mean below 146 pounds? => 7 or 6 or 5 or 8..

The rms speed of an oxygen molecule in a sample at 300 K is about 480m/s. This does not mean that the speed of each molecule is 480 m/s. Many of the molecules have speed less than 480m/s and many have speed more than 480m/s. Maxwell derived an equation giving the dist..

The rms speed of an oxygen molecule in a sample at 300 K is about 480m/s. This does not mean that the speed of each molecule is 480 m/s. Many of the molecules have speed less than 480m/s and many have speed more than 480m/s. Maxwell derived an equation giving the distribut..

The average age of the employees in an organization is 34 years. Assume the variable is normally distributed and the standard deviation is 4. If 25 employees are selected at random, then find the probability that the sample mean age of the employees is less than 35 yea..