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In: Statistics and Probability

The introductory biology class at a large university is taught to hundreds of students each semester....

The introductory biology class at a large university is taught to hundreds of students each semester. For planning purposes, the instructor wants to find out the average amount of time that students would use to take the first quiz if they could have as long as necessary to take it. She takes a random sample of 100 students from this population and finds that their average time for taking the quiz is 20 minutes, and the standard deviation is 10 minutes.

a). Compute the standard error of the mean (SEM) for the average time to take this quiz in a minute.

b). the lower limit of 95% confidence interval for the average time to take this quiz is?

c). the upper limit of 95% confidence interval for the average time to take this quiz is?

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