After numerous studies, it is estimated that the age of college students follows a normal distribution...

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After numerous studies, it is estimated that the age of collegestudents follows a normal distribution with a mean of 20.7 yearsand a standard deviation of 1.8 years. A random sample of 16college students is taken and the sample mean and sample standarddeviation are found to be 21.5 years and 2.5 years,respectively.
a. Is the sample average of 21.5 considered an outlier (in otherwords, what is the chance of getting a sample mean at least aslarge as 21.5)?
b. The calculated value of the sample standard deviation islarger than Ïƒ, is 2.5 years enough larger than 1.8 that theestimate of Ïƒ does not seem reasonable?
c. No matter what you got for an answer in part b, assume we nolonger trust Ïƒ = 1.8 to be valid. Calculate the same probability asyou did in part a, but this time, assume that Ïƒ is unknown.
d. Is there a significant difference in parts A and C?

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Solutiona Is the sample average of 215 considered an outlier in otherwords what is the chance of getting a sample mean at least aslarge as 215Answer It is required to findUsing the zscore formula we haveNow using the standard normal table we See Answer

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