Question

Del Delivery delivers sandwiches to neighboring office buildings during lunch time in New York City. The dell that the sandwiches be delivered within 20 minutes from receiving the order. Given the hectic schedules of their customersconsistent delivery time a must. The owner decided that the standard deviation of delivery times should be at most 5 minutes. To determine how consistently the sandwiches are being delivered the manager randomly selects 23 orders and measures the time from receiving the order to delivery of the sandwich. The average time to dellvery of the sample was 21 minutes with a standard deviation of 12.69 minutes. Will the manager conclude at = 0.01 that the delivery times vary more than the owner desires?

Step 1: Calculate the statistic for this problemRound your answer to two decimal places a = 0, 0 degrees

Step 2: Calculate the P-value for an upper-sided alternative hypothesis (right-tailed test)

Step 3: What is the rejection at the 0.01 level of significance for the test on the variance for a lower-tailed alternative hypothesis (left-tailed test?)

Step 4: State conclusion using a significance level of 0.01.

Step 5: Calculate a 90% confidence interval for the variance of delivery times.

Answer 1