View the step-by-step solution to:

- It was found that in a sample of 90 teenage boys, 70% of them have received speeding tickets.

- It was found that in a sample of 90 teenage boys, 70% of them have received speeding tickets.
What is the 90% confidence interval of the
true proportion of teenage boys who have received
speeding tickets?

- Dr. Christina Cuttleman, a nutritionist, claims that the average number of calories in a serving of popcorn is 75. A sample of 50 servings of popcorn yields an average of 78 calories with a standard deviation of 7. Conduct a hypothesis test using the traditional method to determine if evidence exits to reject Dr. Cuttleman’s claim at a = 0.05.

- A recent gasoline survey said the national average price of gasoline was $2.384 a gallon. It was felt that gasoline in Missouri was significantly lower than the national average. A survey of 30 different communities in Missouri found the average price of gasoline to be $2.329 a gallon with a standard
deviation of $0.152. Conduct a hypothesis test using the P-valuemethod with a=.05 to determine if the price of gas in Missouri is less than the national average.

- Melvin says his average golf score is 75. Melvin lies a lot, and you claim his average score is higher than 75. So, you observe his game for a random sample of ten rounds and find that the sample mean is 78 strokes with a sample standard deviation of 4 strokes. At the .05 level should you believe Melvin or have him barred from the country club?

- U.C.L.A. states that at least 40% of the students live on campus. From a sample of 250 students, 90 live on campus. Does this sample provide evidence that fewer than 40% live on campus? Conduct the test with a=0.01.

- John Davis, a manager of a supermarket, wants to
estimate the proportion of customers that will be using food stamps at his store. How large a sample is required to estimate the true proportion to within 5% with 90% confidence?

This question was asked on May 13, 2010.

Recently Asked Questions

Why Join Course Hero?

Course Hero has all the homework and study help you need to succeed! We’ve got course-specific notes, study guides, and practice tests along with expert tutors and customizable flashcards—available anywhere, anytime.


Educational Resources
  • -

    Study Documents

    Find the best study resources around, tagged to your specific courses. Share your own to gain free Course Hero access or to earn money with our Marketplace.

    Browse Documents
  • -

    Question & Answers

    Get one-on-one homework help from our expert tutors—available online 24/7. Ask your own questions or browse existing Q&A threads. Satisfaction guaranteed!

    Ask a Question
  • -


    Browse existing sets or create your own using our digital flashcard system. A simple yet effective studying tool to help you earn the grade that you want!

    Browse Flashcards