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 conclusion for this hypothesis test would be that because the test statistic is . a. more than the critical value, we can conclude that the proportion of United Airline flights that arrive on-time is more than 0.90
b. more than the critical value, we cannot conclude that the proportion of United Airline flights that arrive on-time is less than 0.90
c. less than the critical value, we can cannot conclude that the proportion of United Airline flights that arrive on-time is less than 0.90
d. less than the critical value, we can conclude that the proportion of United Airline flights that arrive on-time is less than 0.90

d. less than the critical value, we can conclude that the proportion of United Airline flights that arrive on-time is less than 0.90

Step-by-step explanation:

Expedia would like to test the hypothesis that the proportion of Southwest Airline flights that arrive on-time is less than 0.90.

At the null hypothesis, we test that the proportion is of 0.9, that is:

At the alternate hypothesis, we test that it is less than 0.9, that is:

The test statistic is:

In which X is the sample mean, is the value tested at the null hypothesis, is the standard deviation and n is the size of the sample.

0.9 is tested at the null hypothesis:

This means that

A random sample of 140 United Airline flights found that 119 arrived on-time.

This means that

Value of the test-statistic:

P-value of the test and decision:

The p-value of the test is the probability of finding a sample proportion of 0.85 or less, which is the p-value of z = -1.97.

Looking at the z-table, z = -1.97 has a p-value of 0.0244.

The p-value is 0.0244 < 0.05, which means that the test statistic is less than the critical value, and thus, we can conclude that the proportion of United Airline flights that arrive on-time is less than 0.90.

The correct answer is given by option d.

step-by-step explanation:

the thermometer is precise but not accurate

step-by-step explanation: