Sampling Distributions

The Gallup Poll asked a random sample of 1785 adults whether they attended church during the past week.  Let p-hat be the proportion of people in the sample who attended church.  A newspaper report claims that 40% of all U.S. adults went to church last week.  Suppose this claim is true. 
What is the mean of the sampling distribution of p-hat?

• 0.4
• 0.44
• 0.56
• 0.6

What happens to the shape of a sampling distribution of sample means as n increases?

• It becomes narrower and bimodal.
• It becomes narrower and more normal.
• It becomes wider and skewed right. 
• It becomes wider and more normal. 

These symbols represent the mean and standard deviation for which of the following distributions?

• The Population
• The Sample
• The Sampling Distribution
• Sampling Frame

The mean and standard deviation of a population are 200 and 20, respectively. Sample size is 25. 
What is the standard deviation of the sampling distribution?

• 200
• 16
• 25
• 4

At a particular college, 78% of all students are receiving some kind of financial aid.The school newspaper selects a random sample of 100 students and 72% of the respondents say they are receiving some sort of financial aid. Which of the following is true?

•  78% is a population and 72% is a sample.
• 72% is a population and 78% is a sample
• 78% is a parameter and 72% is a statistic
• 72% is a parameter and 78% is a statistic

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 deviation of the sampling distribution if n is 25.

• μ_x-bar = 2.51, σ_x-bar = 0.06
• μ_x-bar = 2.51, σ_x-bar = 0.084
• μ_x-bar = 0.52, σ_x-bar = 0.084
• μ_x-bar = 2.51, σ_x-bar = 0.42

The mean weight of potato chip bags is 10.5 ounces with a standard deviation of 3 ounces. A random sample of 40 bags of potato chips is selected. What is the probability that the mean of the sample is less than 10 ounces?

• P = -1.05
• P = .1469
• P = .0202
• P = .8531

The mean distance an NHS student travels to school is 5.6 miles with a standard deviation of 1.7 miles. Ms. Landry finds the mean of her 4th period class - a randomly selected sample of 29 students. What is the probability that the mean of her class is less than 6 miles?

• P = 0.00
• P = 0.1020
• P = 0.8980
• P = 1.27

If you are to find P (x̄ ≥ 10) that means

• the probability that the sample mean is less than 10
• the probability that the sample mean is no more than 10
• the probability that the sample mean is at least 10
• the probability that the sample mean is more than 10

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

• Normal Distribution
• Binomial Distribution
• Sampling Distribution
• Uniform Distribution