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OpenStax, Introductory Statistics 2e §11.6 Test of a Single Variance · Exercise 10 · Statistics · Chi-square tests

Test of a Single Variance · Exercise 10

The average waiting time in a doctor’s office varies. The standard deviation of waiting times in a doctor’s office is 3.4 minutes. A random sample of 30 patients in the doctor’s office has a standard deviation of waiting times of 4.1 minutes. One doctor believes the variance of waiting times is greater than originally thought.

What can you conclude at the 5% significance level?

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OpenStax, Introductory Statistics 2e · §11.6 Test of a Single Variance · Exercise 10

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