1. Question: In a random sample of 350 attendees of a minor league baseball game, 184 said that they bought food from the concession stand. Create a 95% confidence interval for the proportion of fans who bought food from the concession stand. Use Excel to create the confidence interval, rounding to...
Understanding Confidence Intervals – Excel
Week 6
1. In a random sample of 350 attendees of a minor league baseball game, 184 said
that they bought food from the concession stand. Create a 95% confidence interval for
the proportion of fans who bought food from the concession stand. Use Excel to create the
confidence interval, rounding to four decimal places. 0.4734 < P < 0.5780
2. Alison, the owner of a regional chain of pizza stores, is trying to decide whether to add
calzones to the menu. She conducts a survey of 700 people in the region and asks
whether they would order calzones if they were on the menu. 46 people responded “yes.”
Create a 90% confidence interval for the proportion of people in the region who would
order calzones if they were on the menu.Round your answer to four decimal places.
0.0503 and 0.0811
3. A company wants to determine a confidence interval for the average CPU time of its
teleprocessing transactions. A sample of 70 random transactions in milliseconds is given
below. Assume that the transaction times follow a normal distribution with a standard
deviation of 600 milliseconds. Use Excel to determine a 98% confidence interval for the
average CPU time in milliseconds. Round your answers to the nearest integer and use
ascending order.
(5,906, 6,240).
4. A sample of 22 test-tubes tested for number of times they can be heated on a
Bunsen burner before they crack is given below. Assume the counts are normally
distributed. Use Excel to construct a 99% confidence interval for μ. Round your answers
to two decimal places and use increasing order.
(1071.77, 1477.33).
5. Question
Suppose that the scores of bowlers in a particular league follow a normal
distribution such that the standard deviation of the population is 12. Find
the 95% confidence interval of the mean score for all bowlers in this league
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Milestonee. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $20.57. You're not tied to anything after your purchase.
