Hypothesis Testing with One Population
The credit manager of a discount department store believes that the average age of his charge account customers is less than 40 years. A random sample of 100 charge account customers revealed an average age of 36 years and a standard deviation of 10 years. Do these data provide sufficient evidence to support the credit manager's belief? (Use 95% confidence)
Hypothesis Testing with One Population The credit manager of a discount department store believes that the...
A department store manager believes that the average age of their customers is at least 60. To prove their point, the manager randomly selects a sample of customers and records their ages. The data is listed below. At α = 0.01, test the manager's claim. 70 48 41 68 69 55 70 57 60 83 32 60 72 58 88 48 59 60 56 65 66 60 68 42 57 59 49 70 75 63 44
A sporting goods store believes the average age of its customers is 36 or less. A random sample of 49 customers was surveyed, and the average customer age was found to be 38.3 years. Assume the standard deviation for customer age is 8.0 years. Using α=0.05, complete parts a and b below.a. Does the sample provide enough evidence to refute the age claim made by the sporting goods store?
A sporting goods store believes the average age of its customers is 38 or less. A random sample of 39 customers years. Using a = 0.01, complete parts a and b below. a. Does the sample provide enough evidence to refute the age claim made by the sporting goods store? Determine the null and alternative hypotheses. Нор Hyu The z-test statistic is (Round to two decimal places as needed.) The critical z-score(s) is(are) (Round to two decimal places as needed....
A lecturer believes that less than 40% of all students understand hypothesis testing. To determine whether or not there is strong evidence to support his belief he tests a random sample of 50 students which shows the proportion of students who understand hypothesis testing to be 28%. The lecturer would A.not reject Ho at 5% but reject Ho at 1% level of significance B.reject Ho at 5% but not reject Ho at 1% level of significance C.reject Ho at both...
A sporting goods store believes the average age of its customers is 37 or less. A random sample of 44 customers was surveyed, and the average customer age was found to be 39.8 years. Assume the standard deviation for customer age is 7.0 years. Using a = 0.05, complete parts a and b below. a. Does the sample provide enough evidence to refute the age claim made by the sporting goods store? Determine the null and alternative hypotheses. Ho: H4:
In examining the credit accounts of a department store, an auditor would like to estimate the true mean account error (book value – audited value). To do so, the auditor selected a random sample of 50 accounts and found the mean account error to be $60 with a standard deviation of $30. a. Construct a 95% confidence interval for the population mean account error. What conclusion can be made from this confidence interval? b. How large a sample is actually...
help! In examining the credit accounts of a department store, an auditor would like to estimate the true mean account error (book value – audited value). To do so, the auditor selected a random sample of 50 accounts and found the mean account error to be $60 with a standard deviation of $30. a.Construct a 95% confidence interval for the population mean account error. What conclusion can be made from this confidence interval? b.How large a sample is actually needed...
A national business magazine reports that the mean age of retirement for women executives is 61.0. A women’s rights organization believes that this value does not accurately depict the current trend in retirement. To test this, the group polled a simple random sample of 95 recently retired women executives and found that they had a mean age of retirement of 61.5. Assuming the population standard deviation is 2.5 years, is there sufficient evidence to support the organization’s ...
QUESTION 10 A large regional department store is evaluating the effectiveness of its credit card program, which costs it approximately $1m per year to administer. The store believes that for the credit card program to be worthwhile, the administrative costs should be no more than 10% of the total of the average annual account balances. Rather than reviewing each of the 15,000 individual accounts, the store's analysts randomly selected a sample of 500 average annual balances from the frame. The...
QUESTION 27 The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in the sample to check out was 55 minutes and the sample standard deviation was 2 minutes. We want to test to determine whether or not the mean waiting time of all customers is significantly more than 5 minutes The hypothesis to test the manager's concern is: Hops 5, Ha>5 The test statistic is a...