Expedia would like to test the hypothesis that the proportion of Southwest Airline flights that arrive on- time is less than 0.90. A random sample of 140 United Airline flights found that 119 arrived on- time. Expedia would like to set α = 0.05. The p- value for this hypothesis test would be ------.
A)0.0244
B)0.0664
C)0.0872
D)0.0137

Question

Quizplus · Accepted Answer

The p-value is calculated using a one-sample proportion z-test. The null hypothesis is that the proportion of on-time flights is 0.90, and the alternative hypothesis is that the proportion is less than 0.90. With 119 out of 140 flights arriving on time, the sample proportion is 119/140 = 0.85. Using the formula for the test statistic and finding the corresponding p-value in the standard normal distribution, the p-value is closest to 0.0244, indicating the probability of observing a sample proportion of 0.85 or less if the true proportion is 0.90.

Expedia Would Like to Test the Hypothesis That the Proportion