A researcher claims that the mean SAT scores is greater than 515. A sample of 1800 students shows the sample mean SAT scores is 519 and sample standard deviation is 111. Test the claim at 0.1 level of significance.
(a) State the null and alternative hypotheses.
(b) Calculate test statistic.
(c) Find critical value.
(d) state a conclusion based on the results in part (b) and part (c)