A university wants to determine the average distance that commuter students travel to get to class with an error of ±3 miles and 90 percent confidence. What sample size would be needed, assuming that distances are normally distributed with a range of X = 0 to X = 50 miles, and using the Empirical Rule ±3 to estimate ?
Answer
about 28 students
about 47 students
about 30 students
about 21 students.