A clothing store manager takes a random sample of 40 sales for the day. From this sample, the manager calculated that the mean sale amount per customer was $88 with a standard deviation of $12. Assume that sales per customer are approximately normally distributed. Construct a 99% confidence interval for the mean sales per customer. $82.90 to $93.10
Added by Rosario S.
Step 1
Sample mean (x̄) = $88 Sample standard deviation (s) = $12 Sample size (n) = 40 Show more…
Show all steps
Close
Your feedback will help us improve your experience
Adi S and 61 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
The manager of a small shopping mall wants to estimate the mean amount spent per shopping visit by customers. He computed a 95% confidence interval based on a sample of 36 customers as (120, 305). What is the sample mean? use online calculator if needed An analyst in a personnel department randomly selects the records of 57 hourly employees and finds that the mean wage rate per hour is 44 with a standard deviation of 11. Find the lower confidence limit of the 90% confidence interval estimate for the mean wage of all hourly employees. Round your answer to two decimal places. use online calculator if needed
Charles M.
Suppose that a random sample of 18 recently sold houses in a certain city has a mean sales price of $290,000, with a standard deviation of $11,000. Under the assumption that house prices are normally distributed, find a 95% confidence interval for the mean sales price of all houses in this city. Give the lower limit and upper limit of the 95% confidence interval.
Christopher S.
Jordan is the manager of a used bookstore. He wants to estimate the average amount a customer spends per visit. A random sample of 20 customer receipts had a mean of x ? = $6.90. Suppose the sample standard deviation of the 20 receipts was s = $2.10. Find a 90% confidence interval for the average spent by all customers. (round to 2 decimal places)
Ameer S.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD