National average ACT score for high school students stands at 25. A teacher thinks that her students perform better than average. So she collects data for 32 students and finds out that their average is 26.5 with standard deviation 3.7.
(a) Set up a hypothesis test to see whether the teacher is right
(b) Construct a 95% confidence interval for the mean ACT score. Explain your choice of distribution in constructing the confidence interval (normal or t-distribution).
(c) Find the p-value for the test. What is your decision on the teacher’s claim?


National average ACT score for high school students stands at 25. A teacher thinks that her...
The Mean ACT score for 43 male high school students is 21.1 with a standard deviation of 5.0. The mean ACT score for 56 female high school students was 20.9 with a standard deviation of 4.7. Test the claim that male and female students have equal test scores. Test at a level of significance of 0.01 Make sure you give an answer for each of the following: a) Claim in symbols and labeled Ho or Ha and labeled as the...
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