In the belief that Statistics is too hard, a student claims that the mean score on a final exam is less then 70. 15 scores will be chosen at random to test this claim. Assume that scores on statistics tests are approximately normally distributed. Express the claim in symbolic form. State the null and alternative hypothesis for this situation.
1) The scores slected at random are: 79.5 87.5 80.0 84.0 88.0 45.5 43.5 91.5 93.5 38.00. Compute the test statistic for this test.
2) Compare a p-value for this test
3) At a 0.10 level of significance, what is the decision for this test?
4) State the conclusion in plain language.
5) Based on the data, find a 95% confidence interval for the mean value of grades the final exam.