Suppose a new standardized test is given to 100 randomly selected third-grade students in Connecticut. The...

Suppose a new standardized test is given to 100 randomly selected third-grade students in Connecticut. The sample average score x¯ on the test is 58 points, and the sample standard deviation, sx, is 8 points.

2.1 The authors pan to administer the test to all third-grade students in Connecticut. Construct 95% confidence interval for the mean score on all Connecticut third graders. (5 points)

2.2 Suppose the same test is given to a 200 randomly selected third graders from Iowa, producing a sample average of 62 points and sample standard deviation of 11 points. Construct a 90% confidence interval for the difference in mean scores between Connecticut and Iowa. (10 points)

2.3 Can you conclude with a high degree of confidence that the population means for Iowa and Connecticut students are difference? (10 points)

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orchestra answered 1 year ago

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