In 2013, the average length of a feature length film was 86 minutes with a standard...

In 2013, the average length of a feature length film was 86 minutes
with a standard deviation of 24 minutes. Source: IMDB.com/interfaces
a) Explain why it is inappropriate to use the normal model to find the probability
that a random sample of 15 films will have a mean length greater than 115
minutes.
b) Describe the sampling distribution of x for n = 40 films (Shape, Center,
Spread, with justification).
c) Using the Standard Normal Table, find the proportion of samples of size
n = 40 that will have a mean length greater than 115 minutes.
d) Will the proportion found in c) be greater than or less than the proportion of
samples of size n = 65 that will have a mean length greater than 115 min?
Explain.
e) There is a 4% probability that a random sample of 40 films will have a mean
length greater than ______. (Use the Standard Normal Table.)

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Expert Solution

orchestra answered 1 year ago

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