A random sample of 78 eight grade students' scores of 287. This test result prompts a state school administrator yo declare that the mean score for the state's eight graders on this exam is more than 280. Assume that the population standard deviation is 40. At a =0.02, is there enough evidence to support the administrator's claim? Given Ho and Ha: Ho: u<_280 Ha: u>280 (claim) i) Find the standardized test statistic z, and its corresponding area. ii) Find tge P-value. iii) Decide whether to reject or fail to reject the null hypothesis. iv) Interpret your decision in the context of tge original claim.

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