Question

A pizza place recently hired additional drivers and as a result now claims that its average delivery time for orders is under 45 minutes. A sample of 39 customer deliveries was? examined, and the average delivery time was found to be 41.9 minutes.? Historically, the standard deviation for delivery time is 10.6 minutes. Using ? = 0.10?, complete parts a-c

z-test statistic=

critical z-score=

p-value=

Answer 1

Solution :

Given that,

= 41.9

=45

= 10.6

n = 39

This is the two tailed test .

The null and alternative hypothesis is ,

H₀ :   = 41.9

H_a :     41.9

Test statistic = z

= ( - ) / / n

= (45-41.9) /10.6 / 39

= 1.83

z-test statistic= 1.83

critical z-score = The significance level is α = 0.10, and the critical value for a two-tailed test is z_c = 1.64

p-value = 0.0678