Understanding Sampling Distributions and Probability

The video tutorial explains how to determine the probability that more than 10% of a sample of students report experiencing extreme stress, given a known population proportion of 15%. It covers the concept of sampling distribution, conditions for normality, and the calculation of mean and standard deviation. The tutorial concludes with a demonstration of using a normal cumulative distribution function to find the desired probability.

What percentage of students at the school are known to have experienced extreme stress?

• 20%

• 25%

• 15%

• 10%

How many students were surveyed by the high school newspaper?

• 160

• 150

• 170

• 180

What is the rule of thumb to determine if a sampling distribution is approximately normal?

• Sample size must be less than 10

• Sample size times population proportion must be greater than or equal to 10

• Sample size times population proportion must be less than 10

• Sample size must be greater than 100

What is the mean of the sampling distribution in this scenario?

• 0.10

• 0.15

• 0.20

• 0.25

How is the standard deviation of the sampling distribution calculated?

• Square root of N times (1-P)

• Square root of P times N

• Square root of P times (1-P) over N

• P times (1-P) over N

What is the approximate standard deviation of the sampling distribution?

• 0.018

• 0.028

• 0.038

• 0.048

What is the probability that more than 10% of the sample reports stress?

• 66%

• 86%

• 76%

• 96%

What function is used to calculate the probability in a normal distribution?

• Normal PDF

• Normal CDF

• Normal IDF

• Normal SDF

What should you specify when using the normal CDF function?

• Only the mean

• Only the standard deviation

• Lower bound, upper bound, mean, and standard deviation

• Only the lower and upper bounds

What is the upper bound used in the normal CDF function for this problem?

• 0.1

• 0.5

• 1

• 0.15