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In: Statistics and Probability

You are interested in the time students usually spend studying for the final exams. Assume that...

You are interested in the time students usually spend studying for the final exams. Assume that the total study time during the final week in the semester among students is approximately Normally distributed with mean= 12 hours and a standard deviation = 4.4 hours . You initially plan to take a simple random sample of size n=50 and compute the average total study time.

  1. What standard deviation of x do you need such that the margin of error for the 95% CI is 0.5 hours?
  2. Using the standard deviation of you calculated in (e), determine the number of students you need to sample such that the margin of error for the 95% CI is 0.5 hours.

Solutions

Expert Solution

if part e value is same as s = 1.80, then sample size would be 50

orchestra answered 1 year ago
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