At a university the historical mean of scholarship examination scores for freshman applications is 800. A...

At a university the historical mean of scholarship examination scores for freshman applications is 800. A historical population standard deviation σ = 150 is assumed known. Each year, the assistant dean uses a sample of applications to determine whether the mean examination score for the new freshman applications has changed.

(a) State the hypotheses.

(b) What is the 95% confidence interval estimate of the population mean examination score if a sample of 90 applications provided a sample mean x = 834?

(c) Use the confidence interval to conduct a hypothesis test. Using α = 0.05, what is your conclusion?

(d) What is the test statistic? What is the p-value?

Expert Solution

a) The appropriate hypotheses are -

against

b)

c) Since the lower bound of the confidence interval < 800, so we reject the null hypothesis at 95% level of confidence or at 5% level of significance and we can conclude that mean of scholarship examination scores for freshman applications has significantly been changed from 800.

d)

milcah answered 4 months ago

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At a university the historical mean of scholarship examination scores for freshman applications is 800. A...

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