Question
In: Statistics and Probability
Grades on a standardized test are known to have a mean of 940 for students in...
Grades on a standardized test are known to have a mean of 940 for students in the United States. The test is administered to 436 randomly selected students in Florida; in this sample, the mean is 952.22 and the standard deviation (s) is 101.52.
a) The 95% confidence interval for the average test score for Florida students is ( 942.67, 961.77). (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 not include mu = 940, so the null hypothesis that mu = 940 (that Florida students have the same average performance as other students in the United States) can be rejected at the 5% level.
c) Another 486 students are selected at random from Florida. They are given a 3-hour preparation course before the test is administered. Their average test score is 957.86 with a standard deviation of 89.30. The 95% confidence interval for the change in average test score associated with the prep course is ( nothing, nothing). (Round your responses to two decimal places.)
Solutions
orchestra answered 1 year agoRelated Solutions
Grades on a standardized test are known to have a mean of 940 for students in...
Grades on a standardized test are known to have a mean of 940
for students in the United States. The test is administered to 436
randomly selected students in Florida; in this sample, the mean
is 952.22 and the standard deviation (s) is 101.52.
The 95% confidence interval for the average test score for
Florida students is (__ , __). (Round your responses to two
decimal places.)
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