Use the following information to answer questions (1) - (5). Feature movie lengths (in hours) were measured for all movies shown in the past year in the U.S. The mean length of all feature length movies shown was 1.80 hours with a standard deviation of 0.15 hours. Suppose the length of a random sample of 20 movies was recorded from all movies released this year. The mean length of the feature length movies was found to be 1.72 hours with a standard
deviation of 0.18 hours.
-If we create a sampling distribution of sample means, what would be the mean and standard deviation of that distribution given the sample size of 20?
A)The mean length would be 1.80 hours with a standard deviation of 0.18 hours.
B)The mean length would be 1.80 hours with a standard deviation of 0.15 hours.
C)The mean length would be 1.72 hours with a standard deviation of 0.18 hours.
D)The mean length would be 1.80 hours with a standard deviation of 0.034 hours.

Question

Quizplus · Accepted Answer

The mean of the sampling distribution of sample means is the same as the population mean, 1.80 hours. The standard deviation of the sampling distribution (standard error) is the population standard deviation divided by the square root of the sample size: 0.15 / √20 ≈ 0.034 hours.

Use the Following Information to Answer Questions (1) - (5)