Ten years ago the mean Ma

Ten years ago the mean Ma

Ten years ago the mean Math SAT score of all high school students who took the exam in a small high school was 490, with a standard deviation of 80. This year, a boxplot of the scores of a random sample of 25 students in the high school who took the exam is given on the next page. The mean score of these students is 530. We assume the population standard deviation continues to be 80. To determine if the is evidence that the scores in the district have improved, the hypothesesHo: u=490, Ha:u>490are tested using the z statistic. With the P-value you find, it may be concluded:a) at the 5% significance level, you have proved the Ho is falseb) at the 5% significance level, you have proved that Ha is falsec) it would have been more appropriate to use a two-sided alternatived) at the 5% significance level, you can reject Ho

%d bloggers like this: