Grades on a standardized test are known to have a mean of 500 for students in...

Grades on a standardized test are known to have a mean of 500 for students in the US. The test is administered to 600 randomly selected students in Florida. In this subsample, the mean is 508, and the standard deviation is 75

i. Construct a 95% confidence interval for the average test score for students in Florida.

ii. Is there statistically significant evidence that students in Florida perform differently from other students in the US?

iii. Another 500 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 514, with a standard deviation of 15. Construct a 95% confidence interval. Is there statistically significant evidence that the preparation course helped? What conditions must be met in order for the results to have a causal interpretation?

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milcah answered 8 months ago

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