assume that the standard deviation of exam scores for a class is 10. We want to...

assume that the standard deviation of exam scores for a class is 10. We want to compare scores between two lab sections. How many exams to detect a mean difference of 10 points between the sections? Solve the problem using power approach(type two error)

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orchestra answered 2 years ago

A) Suppose that the mean and standard deviation of the scores on a statistics exam are...

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PART I Suppose that the mean and standard deviation of the scores on a statistics exam...

PART I Suppose that the mean and standard deviation of the scores on a statistics exam are 78 and 6.11, respectively, and are approximately normally distributed. Calculate the proportion of scores above 74. 1) 0.8080 2) 0.1920 3) 0.2563 4) We do not have enough information to calculate the value. 5) 0.7437 PART II When students use the bus from their dorms, they have an average commute time of 9.969 minutes with standard deviation 3.9103 minutes. Approximately 27.23% of students...

A set of exam scores is normally distributed with a mean = 80 and standard deviation...

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A sample of 10 students record their scores on the final exam for their statistics class....

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