mean of samples

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. III. As sample..

A population consists of the five numbers 2, 4, 6, 8 and 10. Consider all the samples of size 2 that can be drawn with replacement from the population. Find the mean of the sampling distribution means. Also find the difference between the population mean..

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 σ..

The mean for the number of viewers of a sample of entertainment programs is 132, with a variance of 23. The mean for the number of advertisements of a sample of entertainment programs is 182, with a variance of 62. Compare the variations. => The number of vie..

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 5 and 3.05..

In a NBA playoff season the average number of points scored in a game was 200. Assume the standard deviation was 75. If a random sample of 20 games is selected, then what is the probability that the mean of the sample is lesser than 220? => 17.20% or 33.80% or 67.20% o..

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 variable is norm..

A mail order firm professional wishes to estimate the average time taken to deliver the packet(s). How large a sample must she select if she desires to be 90% confident that the true mean is within 3 days of sample mean? The standard deviation of the delivery..

The mean score on a standardized test is 100 with a standard deviation of 8. A random sample of 48 scores was found to have a mean of 98. Find the standard error. => 1.15 or 0.8 or 8.0 or 1.0..

The mean score on a standardized test is 100 with a standard deviation of 8. A random sample of 48 scores was found to have a mean of 98. State the null hypothesis and alternative hypothesis. => H o : The mean score = 100, H a : The mean score ≠ ..