A stationery store wants to estimate the mean retail value of greeting cards that it has in its inventory. A random sample of 121 greeting cards indicates a mean value of $ 3.86 and a standard deviation of $ 0.57. a. Assuming a normal distribution, construct a 90 % confidence interval estimate of the mean value of all greeting cards in the store's inventory. b. Suppose there were 1,000 greeting cards in the store's inventory. How are the results in part (a) useful in assisting the store owner to estimate the total value of her inventory?(Round to two decimal places as needed.)
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A stationery store wants to estimate the mean retail value of greeting cards that it has...
This Question: 1pl Astery store wants to estimate the mean real value of greetrg cards that it has inis inventory A random sample of 121 greeting cards indicates a mean value of 5371 and a standard deviaton of 50 Assuming a normal disbution construct a 90% confidence interval estimate of the mean value of all greeting cards in the store's inventory Suppose there were 2.500 greeting cards in the store's inventory How are the results in part (a) used in...
Question 7 of 21 5 Points Lindsey wishes to estimate the average retail value of the 1000's of greeting cards she has in her store inventory. A random sample of 16 cards yielded an average, X-bar = $4.67, with a sample standard deviation of s = $0.32. Find a 95% confidence interval for the true average retail value of the greeting cards in the store's inventory. O A. $4.67 + 0.17 B. $4.67 + 0.21 OC. $4.67 + 0.16 D....
A marketing researcher wants to estimate the mean amount spent ($) on a certain retail website by members of the website's premium program. A random sample of 98 members of the website's premium program who recently made a purchase on the website yielded a mean of $1200 and a standard deviation of $300. Construct a 99% confidence interval estimate for the mean spending for all shoppers who are members of the website's premium program. (Round to two decimal places as...
A marketing researcher wants to estimate the mean amount spent ($) on a certain retail website by members of the website's premium program. A random sample of 100 members of the website's premium program who recently made a purchase on the website yielded a mean of $2000 and a standard deviation of $200. Construct a 95% confidence interval estimate for the mean spending for all shoppers who are members of the website's premium program. (Round to two decimal places as...
The U,S. Dairy Industry wants to estimate the mean yearly milk consumption. A sample of 16 people reveals the mean yearly consumption to be 60 gallons with a standard deviation of 20 gallons. Assume the population distribution is normal. a. What is the value of the population mean? What is the best estimate of this value? b. Explain why we need to use the t distribution. What assumption do you need to make? c. For a 90% confidence interval, what...
X 8.2.15-T Question Help A marketing researcher wants to estimate the mean savings ($) realized by shoppers who showroom. Showrooming is the practice of inspecting products in retail stores and then purchasing the products online at a lower price. A random sample of 81 shoppers who recently purchased a consumer electronics item online after making a visit to a retail store yielded a mean savings of $57 and a standard deviation of $51. Complete parts (a) and (b). a. Construct...
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A publisher wants to estimate the mean length of time (in minutes) all adults spend reading newspapers. To determine this estimate the publisher takes a random sample of 15 people and obtains the results below. From past studies, the publisher assumes o is 23 minutes and that the population of times is normally distributed 12 9 10 7 9 8 7 12 12 6 11 9 9 Construct the 90% and 99% confidence intervals for the population mean. Which...
- publisher wants to estimate the mean length of time in minutes) all adults spend reading newspapers. To determine this estimate the publisher takes a random sample of 15 people and obtain the results below. From past studies, the bisher assumes als 1.9 minutes and that the population of times is normally distributed 10 12 10 7 10 11 6 7 6 Construct the 90% and 99% confidence intervals for the population mean. Which interval is wider convenient, use technology...
An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within 1.5 years of the population mean. Assume the population of ages is normally distributed. (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 1.6 years. (b) The sample mean is 20 years of age. Using the minimum sample size with a 90% level of confidence,...
An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within 1.7 years of the population mean. Assume the population of ages is normally distributed. (a) Determine the minimum sample size required to construct a 90% confidence interval for the population mean. Assume the population standard deviation is 1.8 years. (b) The sample mean is 20 years of age. Using the minimum sample size with a 90% level of confidence,...