Question

A pizza place recently hired additional drivers and as a result now claims that its average delivery time for orders is under 44 minutes. A sample of 43 customer deliveries was​ examined, and the average delivery time was found to be 40.5 minutes.​ Historically, the standard deviation for delivery time is 11.1 minutes. Using a significance level of 0.10

A. The​ z-test statistic is =

(round to two decimal places)

B. The critical z-score is=

(round to two decimal places)

C. The p-value is=

(round to three decimal places)

(please round to the correct decimal places!!)

Answer 1

Solution :

The null and alternative hypothesis is ,

H0 :   = 44

Ha : < 44

Test statistic (z) =

= ( - ) / / n

= (40.5 - 44) / 11.1 / 43

The​ z-test statistic = -2.07

The critical z-score = z = -1.282

P-value = 0.0224