Question

Deli Delivery delivers sandwiches to neighboring office buildings during lunch time in New York City. The deli claims that the sandwiches will be delivered within 20 minutes from receiving the order. Given the hectic schedules of their customers, consistent delivery time is a must. The owner has 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 delivery of the sample was 21 minutes with a standard deviation of 12.69 minutes. Will the manager conclude at α = 0.01 that the delivery times vary more than the owner desires? Step 2 of 5: Calculate the p-value for an upper one-sided alternative hypothesis (right-tailed test). The alternative hypothesis for this problem is H1:σ2 > 25 mins.

Answer 1

H0: Null Hypothesis:

HA: Alternative Hypothesis:

= 0.01

ndf = n - 1 = 23 - 1 = 22

Rejection Region is :

R = {: > 40.289}

The Test Statistic is given by:

Test Statistic is:

ndf = 22

One Tailed - Right Side Test

From Technology, P - Value = 0.0000

Since P - Value is less than , difference is significant. Reject null hypothesis.

Conclusion:

The manager can conclude at = 0.01 that the delivery time vary more than the owner desires.

Answer to question asked:

The p-value for an upper one-sided alternative hypothesis (right-tailed test) = 0.0000