Sample Distribution

The 300 customers who called the call centre spend an average of 45 minutes on hold, with a standard deviation of 12 minutes. What is the standard error of the sampling distribution for a sample of 150 randomly selected customers?

• 0.70

• 0.69

• 0.58

• 0.49

The heights female college students are normally distributed with mean of 68 inches and standard deviation of 3 inches. If 25 students are randomly drawn from the population, what would be the expected mean of the resulting sampling distribution of the means?

• 88

• 78

• 68

• 58

The heights female college students are normally distributed with mean of 68 inches and standard deviation of 3 inches. If 25 students are randomly drawn from the population, what would be the standard error of the resulting sampling distribution of the means?

• 0.5

• 0.6

• 0.7

• 0.8

In a population of five university students with GPAs of 2.5, 2.3, 1.7, 1.4, and 1.1, a sample of three students are considered. What would be the mean of the resulting sampling distribution?

• 1.8

• 1.9

• 2.0

• 2.1

A distribution showing the sample means of all sample of size n of a population is called

• Binomial Distribution

• Normal Distribution

• Sampling Distribution

• Uniform Distribution

If a sampling distribution of sample means has a sample size less than 30:

• the shape will be Normal

• the shape will not be Normal

• there is no way we can determine the shape

• the shape will be between the shape of the population and Normal

Calculate μ_x-bar and σ_x-bar if μ = 794, σ = 48, and n = 64

• μ_x-bar = 794, σ_x-bar = 0.75

• μ_x-bar =794, σ_x-bar = 6

• μ_x-bar = 12.4, σ_x-bar = 0.75

• μ_x-bar = 99.25, σ_x-bar = 6

The average cost for a gallon of gasoline is $2.51 (source AAA.org) with a standard deviation of $0.42. Find the mean and standard error of the sampling distribution if n = 49

• μ_x-bar = 2.51, σ_x-bar = 0.06

• μ_x-bar = 2.51, σ_x-bar = 0.06

• μ_x-bar = 2.51, σ_x-bar = 0.857

• μ_x-bar = 0.358, σ_x-bar = 0.06

The average cost for a gallon of gasoline is $2.51 (source AAA.org) with a standard deviation of $0.42. Find the mean and standard error of the sampling distribution if n is decreased to 25.

• μ_x-bar = 2.51, σ_x-bar = 0.06

• μ_x-bar = 2.51, σ_x-bar = 0.084

• μ_x-bar = 2.51, σ_x-bar = 0.42

• μ_x-bar = 0.52, σ_x-bar = 0.084

Mr. Szrom's last chemistry test was normally distributed with a mean of 68 and a standard deviation of 12. Random samples of size 16 are drawn from the population. Find the mean of the sample means and the standard error of the sampling distribution.

• μ_x-bar = 68, σ_x-bar = 0.75

• μ_x-bar = 68, σ_x-bar = 3

• μ_x-bar = 17, σ_x-bar = 3

• μ_x-bar = 17, σ_x-bar = 12