Over the past 5 years, the mean time for a warehouse to fill a buyer’s order has been 25 minutes. Officials of the company believe that the length of time has increased recently, either due to a change in the workforce or due to a change in customer purchasing policies. The processing times (in minutes) were recorded for a random sample of 15 orders processed over the past month.
Do the data present sufficient evidence to indicate that the mean time to fill an order has increased?
Answer to relevant QuestionsIf a new process for mining copper is to be put into full-time operation, it must produce an average of more than 50 tons of ore per day. A 15-day trial period gave the results shown in the accompanying table. a. Estimate ...Refer to Exercise 5.67. After a confrontation with the teachers’ union, the state promised to make reimbursements within 60 days. Monitoring of the next 40 resignations yields an average of 58 days, with a standard ...As part of the recruitment of new businesses, the city’s economic development department wants to estimate the gross profit margin of small businesses ( under $ 1 million in sales) currently residing in the city. A ...Random samples of size n1 = 8 and n2 = 8 were selected from populations A and B, respectively. The data are given in the following table. a. Test for a difference in the medians of the two populations using an α = .05 ...Refer to Exercise 6.23. In exercise a. What is the level of significance of the paired t test? b. What is the level of significance of the sign test? c. Place a 95% confidence interval on the mean difference between the ...
Post your question