A professor would like to test the hypothesis that the average number of minutes that a student needs to complete a statistics exam has a standard deviation that is less than 5.0 minutes. A random sample of 15 students was selected and the sample standard deviation for the time needed to complete the exam was found to be 4.0 minutes. The test statistic for this hypothesis test would be _______.
A)8.96
B)17.67
C)13.61
D)10.42

Question

Quizplus · Accepted Answer

The test statistic for testing a hypothesis about a population standard deviation is calculated using the chi-square distribution: χ² = (n-1)(s²/σ²), where n is the sample size, s is the sample standard deviation, and σ is the hypothesized population standard deviation. Here, χ² = (15-1)(4.0²/5.0²) = 8.96.

A Professor Would Like to Test the Hypothesis That the Average