what is the mean of the sampling distribution

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 - ..

The mean weight of girls in grade 12 of school X is 125 pounds, and the standard deviation is 20 pounds. If a sample of 25 girls is selected, then what is the probability that the mean of the sample will be greater than 128 pounds? Assume the variab..

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..

Assume that the weights of 3,000 students at a university are normally distributed with mean 150 pounds and a standard deviation of 7 pounds. If 100 samples of 30 students each are obtained, then what would be the expected mean and standard deviatio..

The average annual salary in a district is $30,000. Assuming that the salaries were normally distributed for a certain group of wage earners with a standard deviation of $5,000, what is the probability that for a randomly selected sample of 70 earners the mean..

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 ..

The average protein content in different types of nuts is 20 g, and the standard deviation is 5 g. Assume the variable is normally distributed. If a sample of 16 nuts are selected, then find the probability that the mean of the sample will be greater than 22 ..

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..

Maxwell's Speed Distribution Law - 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 d..

Mean is the arithmetic average. To find mean of ungrouped data and it is obtained by adding the raw scores and dividing the sum by the number of items. There are three methods to find mean for a frequency distribution. (i) Direct method, (ii..