# Econ 320-Grades On A Standardized Test Are Known To Have A Mean

1. Grades on a standardized test are known to have a mean of 920 for students in the United States. The test is administered to 445 randomly selected students in Florida, in this sample, the mean is 931. 96 and the standard deviation (s) is 99. 36. (a) The 95% confidence interval for the average test score for Florida students is: Lower limit (Round your responses to two decimal places. )Upper limit (Round your responses to two decimal places. )(b) Is there statistically significant evidence that Florida students perform differently than other students in the United States?The 95% confidence interval for the average test score for Florida students (does include, does not include) ?=920,so the null hypothesis that ?=920 (that Florida students have the same average performance as other students in the United States) (can/cannot) be rejected at the 5% level. 2. Compute the following probabilities: If Y is distributed N (-8,9), Pr (Y?-12) = . (Round your response to four decimal places. )If Y is distributed N (-4,9), Pr (Y>-1) = . (Round your response to four decimal places. )If Y is distributed N (40,25), Pr (34?Y?44) = . (Round your response to four decimal places. )