sample mean 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..

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 o..

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..

In a statistical hypothesis testing, the standard deviation of the population is 8, H 0 : μ ≤ 100 and H 1 : μ > 100. Which of the following is true for the sample mean ( X ‾ ) to reject the null hypothesis(H 0 ) at α = 0.01 for a sample..

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 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..

Let P(x,y) and Q(x + D x,y + D y) be two neighbouring points on the curve y = f (x). Let TPT' be the tangent at P, PQ is called the secant of the curve and the slope of secant..

Arithmetic Mean (A.M.) - 1. If a, x, b are in A.P, then x is called the arithmetic mean (A.M.) between the extremes a and b. 2. a. To insert n arithmetic means between two given quantities. Let a and b be any two given quantities, and let A 1 ,A 2 ,..

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..

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..