# Question

A class has 420 students. The final examination is optional-taking it can raise, but cannot lower, a student's grade. Of a random sample of 80 students, 31 indicated that they would take the final examination.

Find a 90% confidence interval for the total number of students in this class intending to take the final examination.

Find a 90% confidence interval for the total number of students in this class intending to take the final examination.

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