# Thread: Need help with this stats problem..

1. ## Need help with this stats problem..

I am confused by this problem because I do not know how to get the standard deviation or mean. How do I solve this.

1. According to an article in News Daily (http://www.newsdaily.com/stories/n22504510-news-airlines-delays/), more than a quarter of U.S. Airlines flights were delayed in 2007. A flight departure is considered late if it departs 15 minutes or more beyond its scheduled departure time.

a. In a random sample of 500 Southwest Airlines flights departing Phoenix Sky Harbor Airport in January 2008, 141 departed 15 minutes or more later than scheduled. At the .05 level of significance, is there evidence that that the proportion of delayed Southwest Airlines departures from Phoenix in January 2008 is greater than 25%?

Complete the following:
1. State H0.

2. State H1.
3. State the value of α.
4. State the value of the test statistic.
5. State the p-value.

6. State the decision in terms of H0 and why.
7. State the decision in terms of the problem.

b. Explain the meaning of the p-value in this problem.

2. Originally Posted by jetguy35
I am confused by this problem because I do not know how to get the standard deviation or mean. How do I solve this.

1. According to an article in News Daily (http://www.newsdaily.com/stories/n22504510-news-airlines-delays/), more than a quarter of U.S. Airlines flights were delayed in 2007. A flight departure is considered late if it departs 15 minutes or more beyond its scheduled departure time.

a. In a random sample of 500 Southwest Airlines flights departing Phoenix Sky Harbor Airport in January 2008, 141 departed 15 minutes or more later than scheduled. At the .05 level of significance, is there evidence that that the proportion of delayed Southwest Airlines departures from Phoenix in January 2008 is greater than 25%?

Complete the following:
1. State H0.

2. State H1.
3. State the value of α.
4. State the value of the test statistic.
5. State the p-value.

6. State the decision in terms of H0 and why.
7. State the decision in terms of the problem.

b. Explain the meaning of the p-value in this problem.
There are plenty of websites that explain what to do:

Hypothesis Testing for a Proportion and for Small Samples

AP* Statistics Tutorial: Hypothesis Test for a Proportion

etc.

and I'm sure your textbook and classnotes contain examples as well.